Abstract: Throughout Europe, criminal and extremist milieus are merging, with many jihadis and ‘foreign fighters’ having criminal pasts. An individual’s criminality can affect his process of radicalization and how he operates once radicalized. The Islamic State’s recent propaganda suggests that the group is aware of this reality. It has positively framed the crime-terror nexus by encouraging crime ‘as a form of worship,’ and has been lauding those from criminal backgrounds. This has been reflected on the streets of Europe, where perpetrators have used their criminal ‘skills’ to make them more effective terrorists. While understanding of the crime-terror nexus has developed, there are many knowledge gaps that have practical implications for countering terrorism.
On July 26, 2017, officers from the United Kingdom’s SO15 counterterrorism command arrived at an address in East London to arrest a man for disseminating propaganda. Through several online platforms, Nourdeen Abdullah had been publishing jihadi content. Yet when searching his home and car, police found crack cocaine. Abdullah was charged with two apparently contradictory offenses: disseminating terrorist propaganda and possession with intent to supply Class A drugs.1 a His case reaffirms a pattern seen throughout Europe—as detailed in the authors’ 2016 report “Criminal Pasts, Terrorist Futures”—of criminals, both former and current, becoming involved in jihadism.2
The trend is apparent throughout Europe. From Germany, 66 percent of foreign fighters had police records prior to traveling, according to Federal Police analysis of 778 jihadis.3 In the Netherlands, 64 percent of 319 jihadis—comprising foreign fighters, failed travelers, and those identified as potential travelers—have been subject to criminal reports, according to a study undertaken by a National Police researcher.4 From France, 48 percent of jihadis were already known to the police for delinquency, as per a Coordination Unit of the Fight Against Terrorism (UCLAT) analysis of 265 jihadis from that country believed to have died in Syria and Iraq.5 Meanwhile, from the United Kingdom, at least 47 percent of converts who traveled to Syria had previous criminal convictions, according to a previously unpublished study by a serving Metropolitan Police Officer using official Police National Computer records.b Similarly, a United Nations report highlights the prevalence of criminality among foreign fighters from Austria,6 and officials from Norway told the authors that “at least 60 percent” of their country’s jihadis had previously been involved in crime.7 In short, criminal and extremist milieus routinely overlap.
Is this a new phenomenon? Longitudinal data suggests that criminals-turned-jihadis have existed for over two decades. Marc Sageman’s analysis of al-Qa`ida-affiliated jihadis between the early 1990s and 2003 highlights a Maghreb Arab cluster involved in crime such as theft, trafficking in false documents, and credit card fraud.8 Building upon Sageman’s empirical approach, Edwin Bakker researched 242 jihadis involved in 31 cases of terrorism in Europe from September 2001 to October 2006. He discovered that 52 individuals (or over 21 percent) had a criminal record, with many more being involved in crime yet evading convictions.9 Similarly, Olivier Roy’s database of jihadis in France between 1994 to 2016 shows that almost 50 percent had criminal pasts.10 c Whether this is a new phenomenon or not, it is clear that the nature and dynamics of this crime-terror nexus have been under-researched and poorly understood. There is virtually no academic literature on the subject. On the contrary, until recently, any link between terrorism and crime was routinely dismissed.
The central point is not just that they are criminals, but that their criminality is relevant to their extremism, as it can affect how they radicalize into violence and how they operate once they are radicalized. The authors’ 2016 analysis of 79 European jihadis with criminal backgrounds revealed four themes. Firstly, jihadism can offer redemption from past sins, as well as legitimize further crime. Secondly, prisons offer an environment for radicalization and networking between criminals and extremists. Thirdly, criminals develop skills that can be useful for them as extremists, such as access to weapons and forged documents, as well as the psychological ‘skill’ of familiarity with violence. And finally, white-collar and petty crime is often used to finance extremism. Events since the release of the authors’ 2016 report have reaffirmed these conclusions.
The Islamic State has been embracing these overlaps between criminality and terrorism. The streets of Europe have seen the results of this, with many perpetrators of recent terrorist attacks having criminal pasts. This article examines these developments in three parts: 1) how the Islamic State has been encouraging ‘regular’ crime; 2) cases of criminals-turned-jihadis since the release of the authors’ “Criminal Pasts, Terrorist Futures” report; and 3) developments in the study of the crime-terror nexus.
Embracing the Crime-Terror Nexus
The Islamic State’s magazine Rumiyah has both exalted criminals-turned-jihadis and encouraged the use of crime for jihad. This past summer, its semi-regular obituary feature—titled “Among The Believers Are Men”—lionized a fighter, Macrème Abrougui, after his death on the battlefield in Syria.11 This is typical fare for the magazine. What makes its eulogy of Abrougui unique, however, is just how positively it frames the crime-terror nexus.
The obituary describes how Abrougui—using the kunya Abu Mujahid al-Faransi—was allegedly drawn to jihad from a life of crime. It praises Abrougui for his character even while living as a criminal, transforming from a “fierce gangster” and a “man whom people would fear” to beginning “a new life as a true Muslim.”12 As a prolific criminal, he is said to have amassed “an enormous amount of money through numerous raids on the wealth of the mushrikin [polytheists].”13 It also lays bare his stance toward the authorities: “He wouldn’t care about France’s police officers, as he would have shootouts with them and succeed in escaping from them during his robbery campaigns or when selling drugs.”14 And despite his “indulgence in disobedience and sins,” Abrougui was still “generous in nature and noble in his manners.”15 After all, “he wasn’t afraid of confrontation, nor would he run from a fight.”16 The Islamic State, it seems, not only admires the criminal skillset, but makes it aspirational.
In recounting Abrougui’s first operation with a group of jihadis, the Islamic State also highlights the blurred distinctions between crime and jihadism. In search of money to fund its jihadi activities, the group—“French youth who supported the mujahidin”—located a drug dealer who had apparently hidden €200,000 in his house.17 They stalked the location for days, planning a home invasion with the aim of stealing the cash. For all its similarities to an ‘orthodox’ criminal operation, the Islamic State explained why it was different:
“With most of those possessing experience in this field, it was due to their having entered into the world of robbery and gangs in their previous lives, but the assault this time differed as it was a form of worship by which they sought to draw closer to Allah, not as a means to increase in indulgence in disobedience and corruption.”18
Here the Islamic State seems to be saying to criminals ‘you do not need to change your behavior, only your motivation.’ This could prove to be an incredibly powerful message, as it promises immediate gratification, as well as spiritual legitimation for criminal behavior. It appears as though the group has calculated that for a criminal questioning his lifestyle, this could be a tempting offer, and perhaps explains why many criminals involve themselves in jihadism. It shows the Islamic State as an equal opportunity employer to would-be jihadis, both accepting of past excesses and offering redemption for them. As highlighted in the authors’ 2016 report, these narratives can resonate with criminals.19 In the same way, the Islamic State is in tune with both its members and those it wishes to recruit. The point is not necessarily that Abrougui’s life played out as detailed in the eulogy—there are almost certainly embellishments and omissions—but that the Islamic State acknowledges how relevant the crime-terror nexus is to how many of its would-be recruits operate.
The Islamic State also recognizes the potential for skill transfers between criminal and extremist lifestyles, an effect of the crime-terror nexus highlighted in the author’s 2016 report.20 Simply put, criminals may develop skills and networks that make them more effective as terrorists. Abrougui is a prime example:
“He was administrative-minded and organized, and therefore, he would not devise a plan except that he had prepared for it its means and studied its outcomes and its consequences, and so he would employ this characteristic of his in his operations in an effective way, not breaking into a residence until he had monitored the property thoroughly, and thus if he were to raid the premises he would have considered the worst outcomes and prepared for himself ways to escape from being killed or arrested.”21
The applications of this to an insurgency or terrorist campaign are clear. Such skills transfers continued once in Syria, with Abrougui apparently aiding the Islamic State’s external operations, offering “all his effort, wealth, and information in any jihad-related work that targeted the Crusaders in France.”22 His criminal network and experience would have proved useful for the Islamic State.
In praising Abrougui’s generosity, the Islamic State further acknowledged the use of criminal networks. His eulogy explicitly states that Abrougui would secure forged passports for would-be jihadis who were prohibited from traveling.23 It notes that he himself used a forged passport to travel to Syria.24
Using his street fame and reputation, Abrougui also engaged in outreach, or dawah. In particular, he focused on the youth, “many of whom used to look up to him as an example, due to his previous fame in the criminal world.”25 Despite his use of criminal means to acquire funding, Abrougui warned against involvement in crime: “He would advise them to avoid the path of delinquency, and warn them from getting involved in the affair of drugs—frightening them with Allah’s punishment—and calling them to adhere to Islam and embark upon the straight path.”26
Aside from lauding criminals-turned-jihadis, the Islamic State has also been encouraging crime for the sake of jihad. Another recent issue of Rumiyah heavily encouraged the taking of ghanima (wealth taken through force; i.e., ‘the spoils of war’), fay (wealth taken without force), and ihtihab (wealth taken through fraud and deception).27 This current in jihadi thought is an echo of Anwar al-Awlaki’s exposition in Inspire magazine on the use of ghanima for jihad. The worldview is simple, as outlined by al-Awlaki himself: “Rather than the Muslims financing their jihad from their own pockets, they should finance it from the pockets of their enemies.”28 This economic war is not only a means to finance jihad, but is seen as an end in and of itself: “It is a must on every muwahhid [monotheist] to expand the scope of his jihad to include waging war on the kuffar’s [non-believer’s] wealth.”29 Simply put, jihadis are encouraged to commit crime and steal.
Curiously, it may be unnecessary to finance jihadism with criminal proceeds, given the low costs of terrorism.30 Rudimentary attacks, such as stabbings and vehicle rammings, have very low financial ‘barriers to entry.’ As a result, using crime to raise funds—with its associated risks of detection—is not necessary. As Emilie Oftedal from the Norwegian Defence Research Establishment found, personal assets such as salaries and savings are most frequently used to fund terrorism in Europe, in what is a “remarkably ordinary picture.”31 Yet at least 23 percent of jihadi plots between 2014 and 2016 involved the use of crime to raise funds.32 The authors’ research suggests that radicalized individuals with criminal pasts often continue using the same methods as during their criminal lives. Yet with the Islamic State encouraging crime as the preferred means of raising funds, it can be hypothesized that criminal funding will increase.
Criminals-Turned-Jihadis in Recent Terrorist Plots
Since the release of the authors’ 2016 report, the crime-terror nexus has manifested in several cases on the streets of Europe. The continent has seen both former and active criminals involved in attacks (e.g., Khalid Masood and the March 2017 Westminster attack33) and individuals arrested for both crime and extremism (e.g., Mohamed Lamsalak, for connections to the 2016 Brussels attacks and drug offenses34). This year has also seen the high-profile French ‘Cannes-Torcy’ trial of a network of criminals involved in jihadi plots in 2012, led by Jérémie Louis-Sidney, a drug trafficker turned jihadi.35 These manifestations often mirror the twin themes of redemption and crime as a form of worship as espoused in the Islamic State eulogy for Abrougui.
Today’s terrorist threat in Europe is unprecedented. There are spontaneous attacks by volatile individuals, as well as carefully planned operations by organized cells. The high number of potential perpetrators, with the mobilization of thousands of Europeans to Syria, means that transnational networks are often involved. There is also no uniformity among perpetrators, with attackers ranging from a 40-year-old Ph.D. student36 to three women alleged to have been plotting knife attacks in London.37 The use of technology, for both encryption and propaganda,38 is a further complication, as is the prevalence of firearms in continental Europe.39 The presence of former and active criminals only adds to the threat.
Two attacks during the last year have shown the impact that criminals-turned-jihadis can have: the December 2016 Berlin Christmas market attack and the April 2017 Champs-Élysées attack.
On December 19, 2016, Anis Amri deliberately drove a truck into the Breitscheidplatz Christmas market in Berlin, killing 12 people and injuring 56 others. He was a criminal with a history of convictions for theft and violence and had been imprisoned in Italy for an arson attack. During his incarceration, Amri’s violent behavior led to him spending 70 days in solitary confinement40 and being transferred to three other prisons.41 His behavior in the run-up to the attacks contradicted many stereotypes of a religious fundamentalist. Under surveillance, he was seen dealing drugs in a Berlin park, and during Ramadan, he had taken cocaine and drank alcohol.42 As Georg Heil’s illuminating research into Anis Amri and the Abu Walaa network has shown, this “appears to have led German police to mistakenly conclude that he no longer posed a threat.” That was a fatal miscalculation, as Amri went on to pledge allegiance to Abu Bakr al-Baghdadi and was later celebrated by the Islamic State’s Amaq news agency.43
Amri was the product of a jihadi network in Germany that encouraged crime. Its head was Abu Walaa, whose associate, Fifen Youssouf, is alleged by Lower Saxony police to have committed burglaries encouraged as ghanima for the sake of jihad.44 Amri himself had been involved in crimes such as fraud and theft.45 This legitimization of crime is a perfect mirror of what the Islamic State encourages, and it is a familiar pattern. It has perhaps been most effectively used by Khalid Zerkani in Brussels—responsible for mobilizing up to 72 foreign fighters that traveled to Syria—who told his recruits that “to steal from the infidels is permitted by Allah.”46 Zerkani led a network of criminals, who would rob tourists and commit street crime in Brussels and then use the proceeds to fund their travel to Syria.47 Certainly, this phenomenon is not restricted to the Islamic State—it has antecedents in the Armed Islamic Group’s (GIA) operations in France and the United Kingdom in the 1990s—though the harmony between theory and practice is a noticeable development seen on European streets.
The crime-terror nexus also highlights the potential for ‘skills transfers’ from the criminal world. Karim Cheurfi is a case in point. On April 20, 2017, Cheurfi opened fire on the Champs-Élysées in Paris, killing one police officer before he himself was fatally wounded. In his possession was a note professing support for the Islamic State. His criminal past included robbery and attempted murder, and suggests a highly volatile individual that was familiar with violence. In 2001, Cheurfi was driving a stolen car when he clipped another car, which happened to be driven by a trainee police officer. After a high-speed chase where both cars ended up in a ditch, Cheurfi shot the officer (as well as his passenger-brother) in the stomach. In custody two days later, Cheurfi then seized the gun of an officer who came into his cell and shot him three times before being subdued.48 For these attempted murders, he was sentenced to 15 years. He would see three more convictions: two for violence in detention and one for burglary upon his release.49 He later spoke of his desire to kill police officers to avenge Muslims killed in Syria.50 His volatility made the authorities’ appraisals of his behavior difficult. While his radicalization trajectory is uncertain, his proven ability and will to harm others with deadly violence was a ‘skill transfer’ that he brought over from his criminal career, which may have shortened his mobilization into extremist violence.
Knowledge Advancements and Knowledge Gaps
Just as jihadism has evolved over the past year, so too has understanding of the crime-terror nexus. Of note is the study by David Pyrooz, Gary LaFree, Scott Decker, and Patrick James published in May, comparing 1,473 individuals involved in violent extremism—from across the ideological spectrum—in the United States (from the PIRUS51 database) with 705 gang members (from the National Longitudinal Survey of Youth dataset).52 They found that only six percent of the domestic violent extremists were also involved in gangs, suggesting minimal overlap between the two. Although the American study focuses on gangs rather than all forms of criminality, this brings up the possibility the crime-extremism nexus may be less pronounced in the United States than Europe. More research is needed to assess the degree to which criminal and extremist milieus have merged in the United States.
Yet despite the increased attention to the connections between involvement in both crime and terrorism, empirical works are rare, and much remains outstanding.53 There exist knowledge gaps in three key areas: 1) the process of radicalization; 2) the importance of converts; and 3) the role of prisons.
It is not entirely clear how the process of radicalization affects involvement in crime: does it curtail, cease, or escalate criminality—and what shapes this trajectory? With the Islamic State encouraging crime such as fraud and robbery, it is plausible that an individual’s radicalization will see an escalation in criminality, though this dynamic is far from certain. The poor availability of data means that it is not always possible to compare criminal records before and after involvement in extremism. The situation in Germany, nevertheless, may be indicative of the trend. German Federal Police have released summary statistics on 189 foreign fighters for whom this comparison is possible, revealing that “politically motivated crime” occurs more frequently during the course of their radicalization than prior to their engagement with extremism.54
Convertsd have long been recognized as playing a disproportionate role in jihadi movements, yet few empirical undertakings have analyzed this subset of extremists.55 The same is true of converts among criminals-turned-jihadis.e An unpublished study by Jeremy Moss, a serving Metropolitan Police Officer, offers an invaluable insight.56 The study analyzes the criminality of 143 converts to jihadism from 1992 to 2016, exhaustively identified via open-source research. Their criminal backgrounds were then researched using official Police National Computer (PNC) records. Each individual had a connection to the United Kingdom, whether through citizenship or residency.
The vast majority are male (129 individuals, or 90 percent of the dataset), with few females (14, or 10 percent). As can be expected in a majority-Christian country, 137 (96 percent) of the dataset converted from Christian backgrounds. Just over half were non-white or non-European (78, or 54 percent). The majority traveled, or attempted travel, for terrorist purposes (82, or 57 percent), with the Syrian jihad mobilizing the greatest number (49 completed/attempted travel to Syria, or 37 percent). Foreign nationals feature heavily in the dataset, and so it is likely that additional offending may have taken place elsewhere. The PNC does not always formally record such overseas offending, and so these statistics should be considered as under-reporting the rate of criminality.57
The results are fascinating. In terms of criminality, 75 individuals (52 percent) received at least one crime-related conviction, caution, or a penalty notice for disorder for a criminal matter (i.e., not related to extremism). When extremist activitiesf are included in this measure, the number rises to at least 126 (88 percent). There was a significant contingent of persistent offenders who had over 10 convictions each (24, or 17 percent). Due to difficulties in estimating when a person radicalized, it is often impossible to know whether criminality curtailed, ceased, or escalated during an individual’s radicalization process. Moss estimates that in most cases, petty criminality ceased upon radicalization and was replaced by extremist activities, though the anonymity of the data makes this difficult to verify.
A significant proportion (51, or 36 percent) spent time in prison for ‘conventional’ criminal matters, though it is unknown what exact role incarceration had on their radicalization process. Not only have inmates been radicalized in prison, but they have also established connections and networks that have persisted upon release.
The radicalization of Michael Coe, a member of the proscribed U.K. pro-jihadi al-Muhajiroun organization, is illustrative. He had an eventful criminal career. In 2006, Coe was sentenced to eight years for threatening police with a sawed-off shotgun.58 During this episode, he was already on parole following an earlier conviction for a knifepoint car-jacking and robbery.59 It was while incarcerated that he met an al-Qa`ida-inspired jihadi, Dhiren Barot—himself a convert—who was imprisoned for planning a series of terrorist attacks. Coe radicalized, and did so quickly: “Within [the first] week, the dawah that he gave me, it hit me where no else’s dawah hit me.”60 He changed his name to Mikaeel Ibraheem, and upon release he spoke of his transformation. “When you haven’t got a cause for your life, your life is just like any of these other kuffar—we get up, try to make as much money, sleep with as much women as we can, and do whatever else we can. I have a cause. I want to see the establishment of Khilafah [the caliphate]. I want to see Islamic State.”61 Coe’s example is a confluence of many issues: criminals embracing extremism; radicalization within prisons; and the formation of networks behind the prison walls. Prisons clearly merit closer attention.
The increasing number of extremists passing through the criminal justice system further complicates this issue. In Europe, the number of individuals tried in court for terrorist offenses has steadily increased over the last three years, from 444 individuals in concluded court proceedings in 2014 to 513 in 2015 and 580 in 2016.62 Of those convicted last year, the average sentence in the European Union was only five years.63 With more individuals being processed, and given relatively short sentences, the reality is that evermore extremists will be released from prison. Therefore, the effectiveness of extremist offender management must be examined. There are a host of unresolved questions here.64 What, for example, are the best practices in risk assessments, post-release, and probation arrangements? What is the most effective way to mitigate prison radicalization? And given that European countries are increasingly separating extremist offenders from the general population, how can prison ‘networking’ be minimized?
Many of today’s European jihadis are no longer middle-class intellectuals but petty criminals and former gang members who have spent time in prison and carry convictions for violent crime. All over Europe, criminal and terrorist milieus have merged, producing a crime-terror nexus whose different facets and implications this article has sought to describe.
The existence of this nexus and its associated dynamics should compel researchers, analysts, and policymakers to re-think long-held ideas about how terror, crime, and radicalization have to be countered. At the most basic level, it is worthwhile reexamining easy assumptions about how jihadi radicalization correlates with religious behavior. This echoes the comments of Alain Grignard from Brussels Federal Police, who noted that many of the new generation of jihadis that Belgian and European security agencies were dealing with were radicals prior to their adoption of jihadism.65 Their prior criminality meant they were already accustomed to rebellion against mainstream society and violence against the authorities. This may make their ‘jump’ into political violence that much quicker than would otherwise be the case, and this volatility is worthy of attention. Many of the jihadis studied by the authors were smoking cigarettes, drinking alcohol, or taking drugs after becoming committed to the cause. Many continued to engage in crime. In short, the adoption of the religious worldview of jihadism is no guarantee that criminal behavior has stopped, while acting like a gangster does not preclude involvement in terrorism.
All this means that there are strong arguments for broadening efforts at countering terrorist finance to counter all potential sources of funding, including small-scale and petty crime such as drug dealing, theft, robberies, and the trade in counterfeit goods. Law enforcement agencies need to become more effective at sharing relevant information across departments and “disciplines,” reaching out beyond traditional partners, and making appropriate changes that reflect the new—and multidimensional—nature of the threat.
The new crime-terror nexus that the authors first described in their 2016 report is among the most significant drivers of jihadi radicalization and recruitment today. Recognizing this is key in understanding the nature of the jihadi threat in Europe. CTC
Rajan Basra is a research fellow at the International Centre for the Study of Radicalisation (ICSR). His research focuses on the crime-terror nexus, prisons, and radicalization, and he is a Ph.D. candidate at the Department of War Studies, King’s College London. Follow @rajanbasra
Peter Neumann is Director of the International Centre for the Study of Radicalisation (ICSR). He is also Professor of Security Studies at the Department of War Studies, King’s College London, and currently serves as Chairman’s Special Representative on Countering Violent Radicalisation at the Organization for Security and Co-operation in Europe (OSCE). Follow @PeterRNeumann
[a] Abdullah’s two charges are being processed through the criminal justice system, and therefore, the authors cannot disclose their open-source investigation of his social media footprint.
[b] This is of 36 converts that traveled to Syria, identified using open-sources. Jeremy Moss, unpublished 2017 University of St. Andrews MLitt Dissertation (supervised by Dr. Mark Currie), used with the permission of CSTPV and the Metropolitan Police Service.
[c] Roy’s database contains “about one hundred people involved in terrorism in mainland France and/or having left France to take part in a ‘global’ jihad between 1994 and 2016.” Roy does not state whether there has been a recent increase in the numbers of jihadis with criminal pasts.
[d] It is important to distinguish between a convert (an individual who embraces Islam after originally practicing a different faith, or no faith at all) and a revert (an irreligious Muslim that ‘returns’ to his/her faith). The police researcher looked at converts only, and so this section is not referring to reverts. This was the definition used by Moss, though the authors accept there may be other interpretations.
[e] Converts featured prominently in the authors’ crime-terror nexus database. For more, see Rajan Basra and Peter R. Neumann, “Criminal Pasts, Terrorist Futures: European Jihadists and the New Crime-Terror Nexus,” Perspectives on Terrorism 10:6 (2016): p. 27.
[f] Here “extremist activities” refers to terrorist-related or political violence convictions. The PNC lists each conviction in terms of the offense and circumstance, and so Moss assessed each conviction to see if they were extremism-related. For example, while Dhiren Barot was not convicted of a terrorism offense (he was convicted of conspiracy to murder), his activities were related to a terrorism plot. Similarly, some assaults for religiously motivated offenses (e.g., the so-called ‘Sharia patrols’) were classified as extremist activities, as were violent disorder or affray offenses related to public demonstrations (e.g., al-Muhajiroun activities).
 “Update: Man charged with terrorism offence,” Metropolitan Police, July 28, 2017.
 Rajan Basra, Peter R. Neumann, and Claudia Brunner, “Criminal Pasts, Terrorist Futures: European Jihadists and the New Crime-Terror Nexus,” International Centre for the Study of Radicalisation (ICSR), 2016.
 BKA, BfV, and HKE, “Analyse der Radikalisierungshintergründe und -verläufe der Personen, die aus islamistischer Motivation aus Deutschland in Richtung Syrien oder Irak ausgereist sind – Fortschreibung 2016,” December 7, 2016, p. 18.
 Anton W. Weenink, “Family, Crime, and Mental Health Problems in Jihadis in Police Files,” presentation delivered at NSCR symposium “The Crime-Terror Nexus: Merging Criminological and Psychological Perspectives” in Amsterdam, September 12, 2017. Note that these figures are those of Weenink, a senior researcher at the Dutch National Police, using official police data.
 “Quels sont les profils de 265 djihadistes français tués en Irak et en Syrie?” LCI, September 1, 2017.
 United Nations Analytical Support and Sanctions Monitoring Team, “Analysis and recommendations with regard to the global threat from foreign terrorist fighters,” United Nations, 2015, p. 11.
 Author interviews, Norwegian police officers, September 2016.
 Marc Sageman, Understanding Terror Networks (Philadelphia: University of Pennsylvania Press, 2004), p. 78.
 Edwin Bakker, “Jihadi terrorists in Europe: their characteristics and the circumstances in which they joined the jihad – an exploratory study,” Netherlands Institute of International Relations, 2006, p. 40.
 Olivier Roy, Jihad and Death: The Global Appeal of the Islamic State (London: Hurst, 2017), pp. 20, 28.
 Rumiyah, Issue 11, Al Hayat Media Center, 2017, pp. 44-52.
 Ibid., p. 45.
 Rumiyah, Issue 11, Al Hayat Media Center, 2017, p. 46.
 Basra, Neumann, and Brunner, p. 24.
 Ibid., pp. 35-38.
 Rumiyah, Issue 11, Al Hayat Media Center, 2017, p. 45.
 Ibid., p. 51.
 Ibid., p. 48.
 Ibid., p. 49.
 Ibid., p. 47.
 See Rumiyah, Issue 8, Al Hayat Media Center, 2017, and Rumiyah, Issue 11, Al Hayat Media Center, 2017.
 Inspire, Issue 4, Al-Malahim Media, 2011, p. 60.
 Rumiyah, Issue 11, Al Hayat Media Center, 2017, p. 38.
 For more on this, see Emilie Oftedal, “The Financing of Jihadi Terrorist Cells In Europe,” Forsvarets Forskningsinstitutt (FFI), 2015.
 Oftedal, p. 16.
 Petter Nesser, Anne Stenersen, and Emilie Oftedal, “Jihadi Terrorism in Europe: The IS-Effect,” Perspectives on Terrorism 10:6 (2016): p. 16.
 See, for example, Colin P. Clarke, “Crime and Terror in Europe: Where the Nexis Is Alive and Well,” RAND Corporation, 2016, and Martin Gallager, “‘Criminalised’ Islamic State Veterans – A Future Major Threat in Organised Crime Development?” Perspectives on Terrorism 10:5 (2016).
 “A prisión dos yihadistas que estaban en el aeropuerto de Bruselas durante el atentado,” Mundo, April 27, 2017.
 For more on the Cannes-Torcy network, see Olivier Toscer, “Djihadistes français: comment Jérémy Bailly est devenu Abderrahmane,” L’Obs, November 7, 2012, and Shirli Sitbon, “Anatomy of a Terror Cell: How French Islamist Bombers Recruited a Jew for Jihad,” Haaretz, July 17, 2017.
 “Paris attack: Notre-Dame assailant identified,” BBC News, June 7, 2017.
 “Mother and daughter in court over terror offences and conspiracy to murder,” BBC News, May 11, 2017.
 Colin P. Clarke and Charlie Winter, “The Islamic State may be failing, but its strategic communications legacy is here to stay,” War on the Rocks, August 17, 2017.
 For more on the use of firearms, see Nils Duquet, “Armed to Kill: an exploratory analysis of the guns used in public mass shootings in Europe,” Flemish Peace Institute, June 2016.
 Justin Huggler, Massinissa Benlakehal, and Josephine McKenna, “Everything we know about Anis Amri, the suspected Berlin Christmas market attacker,” Telegraph, December 23, 2016.
 Von Martin Lutz and Constanze Reuscher, “Anis Amri regularly took ecstasy and cocaine,” Welt, January 15, 2017.
 Hannes Heine and Sebastian Leber, “Kokser, Spieler, Gotteskriger,” Der Tagesspiegel, January 26, 2017.
 Chronology on Amri released by the German Federal Interior Ministry; “Warum wurde die Überwachung von Anis Amri abgebrochen?” B.Z., February 2, 2017, cited in Georg Heil, “The Berlin Attack and the ‘Abu Walaa’ Islamic State Recruitment Network,” CTC Sentinel 10:2 (2017): p. 9.
 Case file in the investigation against Hasan Celenk, Boban Simeonovic, and A. Abdulaziz Abdullah, cited in Heil, p. 6.
 Heil, p. 4.
 Pieter Van Ostaeyen and Guy Van Vlierden, “Belgian Fighters in Syria and Iraq – An Important Review of Our Data,” August 3, 2016, published on https://pietervanostaeyen.com/2016/08/03/belgian-fighters-in-syria-and-iraq-an-important-review-of-our-data/. See also Andrew Higgins and Kimiko De Freytas-Tamura, “A Brussels Mentor Who Taught ‘Gangster Islam’ to the Young and Angry,” New York Times, April 11, 2016.
 Pieter Van Ostaeyen, “Belgian Radical Networks and the Road to the Brussels Attacks,” CTC Sentinel 9:6 (2016): p. 9.
 “Une peine allégée pour l’agresseur des policiers,” Parisien, February 16, 2005.
 “Attaque sur les Champs-Elysées: le parcours ultraviolent de Karim Cheurfi,” Monde, April 22, 2017.
 Profiles of Individual Radicalization in the United States, National Consortium for the Study of Terrorism and Responses to Terrorism, University of Maryland.
 See David Pyrooz, Gary LaFree, Scott Decker, and Patrick James, “Cut from the Same Cloth? A Comparative Study of Domestic Extremists and Gang Members in the United States,” Justice Quarterly (forthcoming 2017) for an excellent analysis of the overlaps, or lack off, between gang involvement and extremism in the United States.
 See, for example, Colin P. Clarke, “Crime and Terror in Europe: Where the Nexus Is Alive and Well,” RAND Corporation, 2016.
 “Analyse der Radikalisierungshintergründe und -verläufe der Personen, die aus islamistischer Motivation aus Deutschland in Richtung Syrien oder Irak ausgereist sind,” p. 18-19.
 For a point of entry into this subject, see Bart Schuurman, Peter Grol, and Scott Flower, “Converts and Islamist Terrorism: An Introduction,” International Centre for Counter-Terrorism – The Hague (ICCT), 2016.
 Jeremy Moss, unpublished 2017 University of St. Andrews MLitt Dissertation (supervised by Dr. Mark Currie), used with the permission of CSTPV and the Metropolitan Police Service. The authors are grateful for the permission to use these findings.
 Moss, p. 32.
 “Hero PCs risk their lives to nail gun robber,” Yorkshire Evening Post, February 24, 2006.
 “From Jail to Jihad?” BBC Panorama, May 16, 2014.
 Ibid. Note that Coe said this before the Islamic State declared its so-called caliphate in June 2014.
 “EU Terrorism Situation and Trend Report (TE-SAT),” Europol, 2017, p. 18.
 Ibid., p. 20.
 See “Handbook on the Management of Violent Extremist Prisoners and the Prevention of Radicalization to Violence in Prisons,” Criminal Justice Handbook Series, United Nations Office on Drugs and Crime, 2016, and “Council of Europe Handbook for Prison and Probation Services Regarding Radicalisation and Violent Extremism,” Council of Europe, 2016.
 Paul Cruickshank, “A View from the CT Foxhole: An Interview with Alain Grignard, Brussels Federal Police,” CTC Sentinel 8:8 (2015): p. 8.