Belgian Fighters in Syria and Iraq ~ An Important Review of Our Data

by pietervanostaeyen

pietervanostaeyen | Aug3

August 3, 2016 – by Pieter Van Ostaeyen and Guy Van Vlierden

Belgian fighters in Syria & Iraq – an important review of our data

After a thorough review of our data, we do estimate the total number of Belgian foreign fighters who were active at some point in the current Syrian-Iraqi at 543 individuals now. Almost 70% of them have joined Islamic State, while Shariah4Belgium and the so-called Zerkani network remain the most important recruiters. 127 people have returned to Belgium, while at least 105 were reportedly killed.

We have been keeping track of Belgian foreign fighters for several years now, and we felt that a review of our data was needed. At the time of our very first publication[1], most of the information was vague and much records in our database lacked sufficient identification.

While adding details, the risk of double counting grew. We are pretty confident that the number of fighters not discovered yet, greatly compensated for that. But with all the sources we have now — both publicly available as confidential ones — we thought it would be wise to omit as much of potential doubles as possible.

Therefore, we have reviewed every single entry in our database, investigating the chance that the same person occurred elsewhere. Apart from a rather small number of obvious cases, we finally decided to omit an even number of completely anonymous records dating from before 2014 as the number of fighters we know in detail who had left already at that same time. That is a rather arbitrary measure, but we do believe that it helps to make our estimate more accurate.

On the other hand, we added all the information that we have about minors taken to the battlefield, records that we previously didn’t count. It can be feared that the foreign fighters phenomenon will last for many years, and while the minors of today probably will be the fighters of tomorrow, it  becomes relevant now to count them in.

Definition of Belgian fighters

Altogether, we do estimate the number of Belgian foreign fighters in the current Syrian-Iraqi conflict at 543 now, defining them as follows:

1) every person of Belgian origin, foreign origin but living in Belgium for a significant time, or clearly recruited by an entity operating from Belgium and departed to the conflict zone via Belgian soil;

2) having at least physically tried to reach the war zone of the Syrian-Iraqi conflict that started in March 2011;

3) with a clear intention to join a local fighting party there, be it as a fighter themselves or in any other role.

While it has to be stressed that this definition is broader than Sunni Islamists, actually 534 (or 98% of all our records) can be considered as such. Other kind of affiliations, such as pro-regime fighters in both Syria and Iraq, certainly are a very small part of the foreign figher phenomenon in reality too. But they are also underrepresented in our database because the focus of our active investigations is the Sunni Islamist part.

In the near future, we may try to get a clearer picture of those other kind of affiliations too. More specifically, we would like to add figures about Kurdish fighters, who aren’t included at all for the moment, although we know for sure that they too have Belgian fighters in their ranks. Another possible extension of our database could be the Belgian foreign fighters who have joined Islamic State in Libya.

Our count versus the official one

Although our total estimate is considerably lowered by the review, it is still higher than the number of 458 mentioned by Interior Minister Jan Jambon in April of this year[2]. Probably, authorities do limit their number to fully identified and thus juridically relevant cases, while our database also includes anonymous cases for which the source was deemed reliable. But with much more limited means, we still identified 324 individuals with their full names.

Of all the people in our database, 493 have reached the battle zone — a rate of 90.8%. 32 or 5.9% were stopped somewhere abroad, and 18 or 3.3% before they left the Belgian soil. We have information about 127 people who returned to Belgium — which is slightly higher than the official figures of 114 à 117 mentioned recently[3]. 401 of our records are males, representing 74%. 64 or 12% are females, while the gender is not known for another 78 or 14%.

We have information about 27 children taken to the war zone as minors, of whom at least 18 male and 6 female. These numbers do exclude however youngsters who were juridically still minors at their moment of departure, but apparently have left at their own will. According to official sources, there are at least 48 Belgian minors who have left, of whom 32 were younger than twelve[4].

Islamic State by far the most important group

217 people in our database joined the Islamic State. That is 67.4% of all 322 records for which an exact affiliation is known. Jabhat an-Nusra, the Syrian branch of the global terrorist network al-Qaeda that has rebranded itself into Jabhat Fath as-Sham very recently to indicate a split from al-Qaeda[5], is the second most important group with 43 people for whom it is their last known affiliation.

It must be noted that affiliations often changed in course of time. The third most important group for instance, Majlis Shura al-Mujahideen, became a part of the Islamic State early in 2013. Until then, it was the group joined by almost all the recruits of Shariah4Belgium. Some of them followed their leaders into the Islamic State immediately, while a significant number of others initially switched side to Jabhat an-Nusra. 33 people are still listed in our database with Majlis Shura al-Mujahideen as last known affiliation, because we do not know in which group they landed. But the total number of Belgians who have belonged to Majlis Shura al-Mujahideen at a certain point amounts to 77.

Other Sunni Islamist groups with Belgians in their ranks are Suqur as-Sham (joined by the notorious Brussels based cheikh Bassam Ayachi, and merged in March of last year with Ahrar as-Sham) with 13 people; Katibat al-Khadra and the so-called Katibat des Français with two individuals; and Faylaq as-Sham, Jabhat Ansar al-Din, Jaysh Muhammad, Jund al-Aqsa, Katibat al-Muhajiroun and the Turkistan Islamic Party with each one.

Shariah4Belgium & Zerkani network main recruiters

Looking at recruitment organizations, the Antwerp based Shariah4Belgium still is the most important one. 97 people were at least in touch with that organization before their departure. Second comes the network around the Brussels recruiter Khalid Zerkani, with 72 individuals. An overlap exists, mainly in the circles of the Brussels recruiter Jean-Louis Denis. He worked together with both networks, and has influenced at least 55 people who tried or succeeded to reach the battle zone[6]. The Centre Islamique Belge of the mentioned Bassam Ayachi had proven ties with four fighters, while the so-called ‘Terloplein Group’ and ‘The Way of Life’ — both of which can be considered as spin-offs of Shariah4Belgium — had ties with respectively five and one who’ve tried.

Geographically, the Brussels Capital Region has the highest number of Belgian foreign fighters with 179 individuals on a total of 403 for whom the origin is known, including at least 40 from the now notorious municipality of Molenbeek-Saint-Jean. Antwerp is the second most important place of origin with 98 people, while Vilvoorde (29) and Mechelen (17) add to the importance of the axis Brussels-Antwerp as hotbed of the Belgian jihad[7].

105 deaths, of whom 11 by suicide attacks

Of the Belgian foreign fighers in our database, 105 were reportedly killed. For nine of them, that happened after their return to Europe to commit a terrorist attack: Khalid Ben Larbi and Soufiane Amghar during a police operation on January 15, 2015 in Verviers (Belgium); Bilal Hadfi and Ibrahim Abdeslam while conducting suicide attacks on November 13, 2015 in Paris (France); Abdelhamid Abaaoud and Chakib Akrouh during a police operation following the Paris attacks on November 18, 2015 in Saint-Denis (France); Mohamed Aziz Belkaïd during a police operation on March 15, 2016 in Forest (Belgium); and Najim Laachraoui and Ibrahim El Bakraoui while conducting suicide attacks on March 22, 2016 in Brussels (Belgium).

It has to be stressed that the death of 96 others in the war zone cannot be verified. There are for instance several cases known already of foreign fighters faking their death to lure security services, including the already mentioned Abdelhamid Abaaoud prior to the Verviers plot and the Paris attacks[8]. So, being mentioned in the list of people killed we publish beneath, only means that relevant sources have announced the death of that person, without clear signs that it was inaccurate. Altogether, 11 Belgian fighters have died while committing suicide attacks: six in Iraq, two in France, two in Belgium and one in Syria.

List of Belgian foreign fighters reportedly killed

1. Julian André Harinton, aka Abu Abdullah al-Belgiki, convert from Antwerp who most likely joined the Free Syrian Army and was killed in April 2012

2. Hamdi Mahmoud Saad, a Syrian living in Brussels who joined the Free Syrian Army and was killed in Latakia governorate in August 2012

3. Rustam Gelayev, son of Chechen warlord Ruslan Gelayev who lived a while in Belgium, killed in Aleppo governorate in August 2012

4. Soufiane Chioua, Brussels recruit of Denis & Zerkani networks who left in October 2012, joined Majlis Shura al-Mujahideen and was killed at an unkown date

5. Bilal Zinati, recruit of the Denis network who left in December 2012, joined Majlis Shura al-Mujahideen and was killed at an unknown date

6. Sean Pidgeon, a convert from Brussels recruited by the Denis & Zerkani networks, killed in Aleppo governorate in March 2013

7. Anonymous fighter from Mechelen, killed before April 2013 according to an imam who assisted his family

8. Anonymous fighter from Vilvoorde whose death was announced in April 2013. He was barely eightteen years old and got killed by a sniper two weeks after his arrival in Syria

9. Ahmed Stevenberg, the alias of an unidentified fighter of Jabhat an-Nusra, killed by the Syrian army in the Latakia governorate in April 2013

10. Raphaël Gendron, aka Abdurauf Abu Marwa, a Frenchman raised in Brussels, killed in the ranks of Suqur as-Sham in April 2013

11. Tarik Taketloune, aka Abu Khattab, figher from Vilvoorde who was recruited by Shariah4Belgium and joined Majlis Shura al-Mujahideen, killed in May 2013

12. Saïd Amrani, Denis recruit from the Grand Duchy of Luxembourg who was killed in May 2013

13. Ismail Amgroud, a fighter from Maaseik who joined Majlis Shura al-Mujahideen and was killed in June 2013

14. Noureddine Abouallal, aka Abu Mujahid, a leader of Shariah4Belgium who joined Majlis Shura al-Mujahideen and was killed in July 2013

15. Younis Asad Rahman, the alias of a fighter also known as Asad ar-Rahman al-Belgiki, killed in August 2013 in Latakia governorate

16. Abu Salma al-Belgiki, anonymous fighter killed in August 2013 in Deir ez-Zor governorate

17. Younes Kharbache, Denis recruit from Brussels and brother of Hamza Kharbache. Joined Islamic State and was killed in August 2013 in Damascus governorate

18. Ahmed Daoudi, aka Abu Mochsin, Shariah4Belgium recruit who joined Majlis Shura al-Mujahideen, but reportedly soon switched to a hospital job. Was active as a medical worker during the Al Ghouta chemical attack in August 2013, went missing shortly afterwards and was reported dead

19. Abdel Rahman Ayachi, aka Abu Hajjar, son of the Brussels-Syrian cheikh Bassam Ayachi, killed in the ranks of Suqur as-Sham in September 2013

20. Abdelgabar Hamdaoui, a Shariah4Belgium recruit fighting for Jabhat an-Nusra, killed in September 2013

21. Ahmed Dihaj, aka Abu Ateeq, a leading figure within Shariah4Belgium, who left early in 2013 to join Majlis Shura al-Mujahideen and was killed in the ranks of the Islamic State in September 2013

22. Houssien Elouassaki, aka Abu Fallujah, Shariah4Belgium recruit who became the emir of the foreign chapter within Majlis Shura al-Mujahideen. Switched side to Jabhat an-Nusra and was killed in September 2013

23. Mohamed Bali, aka Abu Hudayfa, Shariah4Belgium recruit coming from Antwerp, killed in the ranks of the Islamic State in September 2013

24. Abdelmonhim R’ha, Sunni Islamist fighter from Antwerp, reportedly a relative of former Belgian Guantánamo detainee Moussa Zemmouri. Killed in September 2013

25. Ibrahim El Harchi, aka Abu Ali, a recruit of Jean-Louis Denis fighting for Islamic State, killed in mid December 2013 during clashes with Ahrar as-Sham in Idlib governorate

26. Sabri Refla, aka Abu Tourab, Denis recruit from Vilvoorde, who subsequently joined Majlis Shura al-Mujahideen and the Islamic State. Committed suicide attack in Iraq in December 2013

27. Abu al-Baraa al-Belgiki, an anonymous fighter of Algerian descent, who served as emir for Islamic State in the Syrian town of Saraqib and was killed there in January 2014

28. Ouafae Sarrar, aka Umm Djarrah, wife of Shariah4Belgium recruit and Islamic State fighter Ilyass Boughalab. Reportedly killed around January 2014

29. Abdelmonaïm Lachiri, aka Abu Sara, recruit of the Zerkani network and a son of its ‘pasionaria’ Fatima Aberkan, killed in the ranks of Jabhat an-Nusra in February 2014

30. Feisal Yamoun, aka Abu Faris, a leader of Shariah4Belgium who left with wife and three young kids, killed in February 2014

31. Hamza Kharbache, Denis recruit from Brussels and brother of Younes Kharbache, who joined the Islamic State and was killed in February 2014 in Aleppo governorate

32. Brahim Labrak, Denis recruit from Brussels with French roots, who joined Majlis Shura al-Mujahideen, switched to Islamic State and was killed in February 2014

33. Nabil Ajraoui, Denis recruit who left as a minor in November 2013 and was killed in February 2014

34. Ilyass Boughalab, aka Abu Djarrah, Shariah4Belgium recruit killed in March 2014 and mentioned afterwards as a member of Islamic State’s elite brigade Katibat al-Battar

35. Yoni Mayne, aka Abu Dujana al-Mali, Zerkani recruit from Brussels with Belgian father and Malinese mother, killed near ar-Raqqah in March 2014 and mentioned afterwards as member of Islamic State’s elite brigade Katibat al-Battar

36. Saïd El Morabit, aka Abu Muthanna, Shariah4Belgium recruit from Antwerp, killed between ar-Raqqah and Hasakah in March 2014 and mentioned afterwards as member of Islamic State’s elite brigade Katibat al-Battar

37. Abdelilah Jab-Allah, aka Abu Omar, Brussels recruit of Denis & Zerkani networks. Joined Majlis Shura al-Mujahideen and was killed in March 2014

38. Karim Mahrach, aka Abu Azzam, recruit of Jean-Louis Denis from Brussels, killed in the ranks of the Islamic State in April 2014

39. Mohamed Said Haddad, Zerkani recruit from Brussels and brother of the Verviers terrorist plot member Abdelmounaim Haddad. Killed in April 2014

40. Khalid Bali, aka Abu Hamza, brother of Mohamed Bali, killed in the ranks of the Islamic State in May 2014 at the age of seventeen

41. Khalid Hachti Bernan, aka Abu Mehdi/Abu Qa’qa, member of Islamic State’s elite brigade Katibat al-Battar, originally from Virton, who was killed in May 2014

42. Nabil Azahaf, aka Abu Sayyaf, Shariah4Belgium recruit from Vilvoorde who became a member of Islamic State’s elite brigade Katibat al-Battar and was killed in May 2014

43. Abu Handalah, anonymous Jabhat an-Nusra fighter who appeared in the video ‘Turning Point’ and was killed in May 2014 near Aleppo

44. Yassine El Karouni, aka Abu Osama, Shariah4Belgium recruit coming from the Netherlands, but living in Antwerp. Joined Majlis Shura al-Mujahideen and was killed in May 2014

45. Kiéran Luce, aka Abu al-Qada al-Faransi, recruit of Denis network coming from the French-Caribbean island of Martinique. Joined Islamic State and committed suicide attack in northern Iraq in May 2014

46. Iliass Azaouaj, an imam from Brussels who left to get Belgian fighters back home, then joined Islamic State himself, but was executed on suspicion of being a spy around July 2014

47. Anonymous Belgian fighter killed in July 2014 in al-Keshkeyyi, Deir ez-Zor governorate

48. Adem Ben Amro, aka Abu Obayda at-Tunisi, Tunisian who lived as refugee in Antwerp, joined the Islamic State in July 2014 and committed a suicide attack in Kobanê at an unknown date

49. Souleymane Abrini, Zerkani recruit and brother of Paris & Brussels attacks accomplice Mohamed Abrini. Joined the Islamic State and was killed in August 2014

50. Abu Jihad al-Belgiki, anonymous Islamic State fighter, killed in battle for airport in Deir ez-Zor governorate in August 2014

51. Zakaria El Bouzaidi, best friend of Sean Pidgeon, who was recruited together with him by the Denis & Zerkani networks. Killed in September 2014

52. Abu Mohsen at-Tunisi, anonymous Belgian fighter of Tunisian descent, fighting for Islamic State and killed in September 2014 during a battle near the airport of Deir ez-Zor

53. Abu Adnan al-Belgiki, anonymous fighter of Algerian descent who switched from Jabhat an-Nusra to Islamic State at the end of 2013 and was killed in September 2014

54. Abu Mohamed al-Belgiki, anonymous fighter killed in October 2014 in Deir ez-Zor governorate

55. Abu Umar al-Belgiki, anonymous fighter of Saudi descent, killed in the ranks of Jabhat an-Nusra in October 2014 in Latakia governorate

56. Abu Yahya al-Belgiki, anonymous member of Islamic State’s elite brigade Katibat al-Battar, killed in October 2014

57. Abu Umar al-Belgiki, anonymous fighter mentioned on a list of deaths of Islamic State’s elite brigade Katibat al-Battar, published in October 2014[9]. It was later confirmed that this kunya doesn’t refer to Abdelhamid Abaaoud, who faked his own death around the same time

58. Abu Sulayman al-Belgiki, anonymous Islamic State fighter of Maghribian descent, killed in Kobanê in November 2014

59. Bilal Barrani, aka Abu Said, Zerkani recruit of French origin who was living in Brussels, joined Islamic State and was killed in December 2014

60. Khongr Pavlovitch Matsakov, Sunni Islamist fighter from Ostend with roots in the Russian republic of Kalmykia, killed in January 2015

61. Abu Taymiyya al-Belgiki, anonymous Islamic State fighter killed in Kobanê in January 2015

62. Khalid Ben Larbi, aka Abu Zoubeyr, Islamic State fighter from Brussels who was killed during a police operation in Verviers (Belgium) on January 15, 2015

63. Soufiane Amghar, aka Abu Khalid, Islamic State fighter from Brussels who was killed during a police operation in Verviers (Belgium) on January 15, 2015

64. Anis Bouzzaouit, aka Abu Ibrahim, a Zerkani recruit who entered the Islamic State’s elite brigade Katibat al-Battar and was killed in February 2015 in Deir ez-Zor governorate

65. Fahd Asamghi, aka Abu Sabir, Shariah4Belgium recruit from Antwerp who subsequently fought for Jaysh al-Muhajirin wa’l Ansar and Jabhat Ansar al-Din. Killed in March 2015

66. Younes Bakkouy, aka Abu Aziz, Islamic State fighter from Genk who left with two brothers, one of whom (and most likely him) was reportedly killed in March 2015 near Tikrit in Iraq

67. Abu Bakr al-Belgiki, anonymous Islamic State fighter from Brussels who committed suicide attack in Ramadi (Iraq) on March 11, 2015

68. Mesut Cankurtaran, aka Abu Abdullah al-Belgiki. Islamic State fighter from Vilvoorde, recruited by Shariah4Belgium and the Denis network. Killed in March 2015 in battle for airport in Deir ez-Zor governorate

69. Karim Kadir, aka Abu Abdullah al-Belgiki. Islamic State fighter from Charleroi, who committed suicide attack at the Iraqi-Jordan border on April 24, 2015

70. Abu Tourab al-Belgiki, anonymous Sunni Islamist fighter from Brussels killed in May 2015 in Damascus governorate

71. Abu Handala al-Belgiki, anonymous Sunni Islamist fighter killed in May 2015

72. Abu Muslim al-Belgiki. Anonymous Islamic State fighter from Antwerp. His death was announced in June 2015, but reportedly happened around a year earlier

73. Sami Ladri, aka Abu Waliya, Zerkani recruit from Brussels who joined the Islamic State and committed suicide attack near an-Nukhayba (Iraq) on June 22, 2015

74. Fayssal Oussaih, aka Abu Shaheed, Islamic State fighter from Maaseik, killed in July 2015

75. Abu Iliace al-Belgiki, anonymous Islamic State fighter whose death was announced by an Islamic State source in ar-Raqqah in July 2015

76. Mossi Junior Juma, teenager from Brussels with roots in Burundi, said to be taken to Syria by his mother and killed in July 2015 at the age of sixteen

77. Lucas Van Hessche, aka Abu Ibrahim, convert from Menen with roots in Haiti, joined Islamic State and was killed in August 2015 in Hasakah governorate

78. Abu Mariyya al-Belgiki, anonymous fighter from Bruges, apparently of Indian descent. Joined Islamic State and was reportedly killed during his very first battle in August 2015

79. Abu Ayman al-Belgiki, anonymous Islamic State fighter, killed by British drone strike in ar-Raqqah in August 2015

80. Brian De Mulder, aka Abu Qasim al-Brazili, convert from Antwerp with Belgian father and Brazilian mother, recruited by Shariah4Belgium. Died in October 2015 of wounds sustained by an air strike three weeks earlier

81. Mohammed Hajji, Islamic State fighter from Antwerp, killed by an air strike in ar-Raqqah in October 2015

82. Abu Abdullah al-Belgiki, anonymous Islamic State figher, killed in October 2015 by a French air strike on a training camp near ar-Raqqah

83. Abdelmalek Boutalliss, aka Abu Nusaybah, Islamic State fighter from Kortrijk who committed suicide attack near Haditha (Iraq) on November 11, 2015

84. Andy Bizala Lubanza, Zerkani recruit from Brussels with Congolese & Rwandese roots, joined Islamic State and was killed in November 2015

85. Anonymous, Belgian wife of Islamic State emir ‘Abu Khabab’ from Saudi Arabia, killed with her husband in November 2015 in Deir ez-Zor

86. Bilal Hadfi, aka Abu Mujahid al-Faransi, Islamic State fighter of French origin living in Brussels, who committed suicide attack in Paris (France) on November 13, 2015

87. Ibrahim Abdeslam, aka Abu Qa’qa al-Belgiki, Islamic State fighter of French origin living Brussels, who committed a suicide attack in Paris (France) on November 13, 2015

88. Abdelhamid Abaaoud, aka Abu Omar al-Belgiki, Zerkani recruit from Brussels, who joined Islamic State’s elite brigade Katibat al-Battar and was killed on November 18, 2015 during a police operation in Saint-Denis (France) linked to the Paris attacks

89. Chakib Akrouh, aka Dhul-Qarnayn al-Belgiki, Zerkani recruit from Brussels, who joined the Islamic State and was killed on November 18, 2015 during police operation in Saint-Denis (France) linked to the Paris attacks

90. Mohammed Jattari, Sunni Islamist fighter from Tienen, killed at unknown date in 2015

91. Younes Ahllal, aka Abu Taymiyah al-Belgiki. Zerkani recruit from Brussels, killed in the ranks of the Islamic State in January 2016

92. Anonymous Belgian fighter killed in the ranks of the Islamic State in Deir ez-Zor governorate on January 20, 2016

93. Abu Umar al-Belgiki, anonymous Islamic State fighter, killed in al-Hawiqa near Deir ez-Zor on January 30, 2016

94. Umm Shérazade al-Belgiki, anonymous woman from Brussels who joined the Islamic State and was reportedly executed for witchcraft in February 2016

95. Anonymous Belgian fighter in the ranks of the Islamic State, reportedly executed for treason in Deir ez-Zor in February 2016

96. Salahuddin al-Belgiki, anonymous Islamic State fighter, who was killed as an important battle commander in Deir ez-Zor governorate in March 2016

97. Mohamed Aziz Belkaïd, aka Abu Abdulaziz al-Jazairi, Islamic State fighter of Algerian descent who was killed on March 15, 2016 during a police operation in Forest (Belgium) linked to the Paris attacks

98. Najim Laachraoui, aka Abu Idriss, Brussels recruit of the Denis & Zerkani networks, who joined the Islamic State and committed a suicide attack at Brussels Airport (Belgium) on March 22, 2016

99. Ibrahim El Bakraoui, Islamic State fighter from Brussels who was stopped on his way to Syria, but committed suicide attack at Brussels Airport (Belgium) on March 22, 2016 (Belgium)

100. Abou Souleyman Belgiki, anonymous fighter from Brussels, who switched side from the Islamic State to Jabhat an-Nusra and was killed near Idlib in April 2016, reportedly by an American drone

101. Abu Anas al-Belgiki, anonymous Islamic State fighter, killed near Mosul (Iraq) in April 2016

102. Abu Dawoud al-Belgiki, anonymous fighter with Jabhat an-Nusra, identified as deputy emir of its foreign fighters in August 2013. Killed by an air strike in May 2016, targeting a meeting of Jabhat an-Nusra leadership at Abu Adh Dhuhur air base in Idlib governorate

103. Abu Abdilah al-Belgiki, anonymous Jabhat an-Nusra fighter of Maghribian origin, killed in June 2016 by a tank attack of the Syrian army near Aleppo

104. Anonymous Belgian fighter, killed as Islamic State commander in a battle near Deir ez-Zor in July 2016

105. Abu Miqdad al-Belgiki, anonymous Islamic State fighter, killed in battle near Deir ez-Zor in August August 2016

[7]   For much more detail on the geographical spread of the Belgian foreign fighter phenomenon, please see http://www.ispionline.it/it/EBook/Rapporto_Hotbeds_2016/Cap.3.pdf