A study published by the King’s College International Centre for the Study of Radicalisation stated that between 140 and 600 European Muslims have gone to Syria since early 2011 to fight the Assad regime, representing 7-11 percent of the foreign fighter total. It appears that most of them come from Great Britain, Germany, Belgium and the Netherlands.
A growing number of European foreign fighters
In April 2013, the German security agencies provided a rough estimate of German fighters in Syria: two to three dozen Muslims have travelled to Syria to join the insurgents. In July 2013, however, Berlin estimated the number of Germans fighting in Syria at more than 70, predicting a further rise in their number in the future. German Muslims have fought in the Syrian cities of Aleppo and Homs, as evidenced by YouTube videos.
Dozens of Belgian Muslims have also joined the opposition forces in Syria. The cases of Belgian teenagers Brian De Mulder (pictured) and Jejoen Bontinck from Antwerp have received public attention because their families have launched a campaign to bring them home; the father of Jejoen Bontinck even travelled to Aleppo to find his son, but in vain.
In addition, up to 100 Dutch fighters have been recruited to fight in Syria.
Acceptance of jihadists among young Muslims
According to a research survey presented by Dutch public television in June 2013, 73 percent of young Dutch Muslims questioned consider these fighters heroes, as opposed to 70 percent of non-Muslims who consider them non-heroes; 81 percent of young Dutch Muslims agree with helping the rebels financially, whereas only 20 percent of non-Muslims agree; finally, 41 percent of young Dutch Muslims agree with sending weapons to insurgents, while only 6 percent of non-Muslims agree.
While the precise number of European jihadists is impossible to pinpoint, counterterrorism officials believe the number of radicals is increasing.
Since 1990, the Muslim population in Europe has expanded from an estimated 10 million to 14 million. Estimates of the number of Muslims in the U.S. range from 2 million to 7 million.
Extremist groups operating in Europe
A 2004 estimate by the intelligence unit of the French police found that about 150 of the country's indexed 1600 mosques and prayer halls were under the control of extremist elements. A study of 1160 recent French converts to Islam found that 23 percent identified themselves as Salafists, members of a sect sometimes associated with violent extremism.
In the Netherlands, home to 1 million Muslims, a spokesman for the Dutch intelligence service says it believes as many as 20 different hard-line Islamic groups may be operating in the country - some simply prayer groups adhering to radical interpretations of the Koran, others perhaps organising and recruiting for violence.
In London, authorities say, as many as 3000 veterans of al-Qaeda training camps over the years were born or based in Britain.
Europol Director General, Rob Wainwright, recently cited 3000 to 5000 EU nationals as potential foreign fighters.
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