The three young Frenchmen were arrested as they tried to make their way to Syria to wage jihad. They had not harmed anyone in France or made plans to do so, according to the evidence at their trial in January, but in France these days, seeking to fight in Syria is enough to bring a charge of plotting terrorism–and in this case sentences of three to five years in prison.
France, and much of Europe, have grown steadily more concerned over the past year about the possibility that the main terrorist threat could come from their own citizens, European passport holders who can move relatively easily between their homelands and the battlefields of Syria, where Islamist rebel groups are fighting the government of President Bashar al-Assad.
In that climate, France is becoming especially aggressive by arresting would-be jihadis even before they leave the country or set foot on a battlefield.
France’s fears came to the fore on Sunday when officials announced the apprehension of a suspect in the killings of three people at the Jewish Museum in Brussels last month, a 29-year-old Frenchman said to have spent time in Syria last year.
On Monday, the French authorities said they had arrested four men they described as jihadi recruiters operating in the Paris region and in the south of France and one French citizen living near Brussels, the latest in a string of cases intended to disrupt the flow of French citizens, usually young men of North African and Arab descent, to Syria.
Interior Minister Bernard Cazeneuve said Monday that he and Justice Minister Christiane Taubira would seek to pass legislation to expand the legal grounds for arrest and prosecution in cases involving plans for terrorist acts, but no violence.
Manuel Valls, the French prime minister, said in January while serving as interior minister that the threat of jihadis returning home to Europe “represents for me, without a doubt, the greatest danger that we must face in the coming years.”
“It’s a phenomenon of unprecedented size,” Mr. Valls said.
Of the 11,000 foreign fighters estimated to be in Syria, as many as 2,000 are from Europe, including 400 to 500 from France, said Peter Neumann, who runs the International Center for the Study of Radicalization at King’s College London, citing figures from several months ago that could be higher now. On Sunday, President François Hollande said about 700 residents of France were fighting or had fought in Syria.
France and Britain have begun to try to use family members as an early warning system to alert authorities when they see signs of a loved one becoming radicalized. Britain has begun a program to detain those who have gone to Syria on their return, charging many of them with terrorism offenses before the suspects have taken any overt action. This year Bosnia put in place a 10-year prison sentence for anyone convicted of trying to fight in a foreign war, a measure clearly aimed at Syria.
France moved earlier and more aggressively than many other nations, in part because of the 2012 case of the terrorist Mohammed Merah.
Mr. Merah, a French Muslim who had trained in Afghanistan, returned to his home city, Toulouse, and killed three French soldiers, three Jewish children and a rabbi who was the father of two of the children.
Before the most recent spate of arrests, including that of Mehdi Nemmouche, the Frenchman arrested in connection with the killings in Brussels, there were more than 50 terrorism-related cases at various stages in the Paris courts, which handle all terrorism cases regardless of where the people are apprehended, Mr. Lestel said.