Europeans are flocking to the war in Syria. What happens when they come home?

By Griff Witte

Word spread quickly last autumn in the rapidly gentrifying north London neighborhood where the Sebah brothers were raised: Mohamed and Akram had died in a car crash.

The news was devastating for friends and neighbors who had watched the brothers grow from affable and popular boys into promising young adults.

But the truth, as recently revealed in jihadist Web site postings, was darker still. Mohamed and Akram had been killed in Syria while fighting alongside militants.

The Sebah brothers were part of a growing legion of Britons who have left behind their often comfortable lives here and joined an increasingly radicalized war effort — one that is just a short budget-airline flight away.

Dozens have been killed. Hundreds more remain on the battlefield. But most disconcerting for British security services are the ones — perhaps 50 or more — who are thought to have come home. British officials have expressed growing alarm in recent days over the possibility that returnees from the Syrian war, hardened and trained by their experiences in battle, will seek to carry out terrorist attacks. The head of Scotland Yard’s counterterrorism command said recently that it is “almost inevitable.”

That concern is matched by a fast-rising tally of arrests, with at least 14 Britons detained on charges related to travel to or from Syria this month, compared to a total of 24 last year.

Security officials say the several hundred Britons who are known to have joined the fight in Syria eclipses the totals for either Afghanistan or Iraq — two other conflicts that attracted radicalized young fighters from the West but that were more difficult to reach. They also acknowledge that there could be many more fighters who have slipped into Syria undetected, given the relative ease of travel by air to Turkey and then over land into the war zone.

The distress among security officials is pervasive in European capitals and in Washington. U.S. intelligence chief James R. Clapper Jr. told a congressional panel Wednesday that the Syrian war had attracted about 7,000 foreign fighters from as many as 50 nations and that at least one of the main jihadist groups in Syria aspires to carry out an attack in the United States.

But Europe is a far closer and more accessible target. The International Center for the Study of Radicalization, or ICSR, estimated last month that nearly 2,000 Western Europeans had traveled to Syria to fight and that the number was rising fast.

French officials say 700 came from France. French Interior Minister Manuel Valls asserted this month that returning fighters represent “the biggest threat that the country faces in the coming years.” The anxiety has been especially acute in Britain, where memories are still fresh of the July 2005 transit bombings. Those attacks, which claimed 52 lives, were carried out by homegrown radicals, at least two of whom had received training in Pakistan.

“The penny hasn’t dropped. But Syria is a game-changer,” Richard Walton, who leads counterterrorism efforts at Scotland Yard, told the Evening Standard newspaper. “We are seeing it every day. You have hundreds of people going to Syria, and if they don’t get killed they get radicalized.”