BERLIN (AP) -- German security services are monitoring about a dozen Islamic extremists who have returned from fighting in Syria and are considered potential terror threats.
Germany's domestic intelligence service said Wednesday that about 300 people -- 280 men and 20 women -- have left Germany for Syria since the start of unrest there more than two years ago.
"There's a growing problem from radicalized and battle-hardened returnees from Syria," Hans-Georg Maassen, the head of the intelligence service, said in a statement. "We have information on about a dozen people who have actively engaged in fighting in Syria. This has increased the risk of terrorist acts in Germany."
Intelligence officials have noted that German law makes it difficult to arrest jihadis returning from Syria unless there is concrete proof that they have committed a crime. But security agencies, wary of letting extremists just slip back into the country, have stepped up their observation of those people considered to be the greatest potential threats.
A senior security official, speaking on condition of anonymity because he was not authorized to discuss the matter by name, said there is strong evidence that about a dozen jihadis who have returned to Germany were trained to use arms and build explosive devices.
So far there is no indication that any of them are planning attacks, he said.
Germany has been one of the main sources in Europe of foreigners fighting in Syria. Of the 300 people who have gone to Syria from Germany, security agencies estimate more than half have engaged in combat and about 20 have died.
There is evidence of German jihadists committing suicide attacks in Syria, the security official said.
While only about 30 of the fighters from Germany are converts, they are among the more radical elements and often used as "cannon fodder" by jihadi groups in Syria, he said.
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