German security official warns of 'abstract' terror threat from returning jihadists

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Germany's domestic intelligence chief says he expects Islamic extremists who have traveled to Syria and Iraq will return and commit terror attacks.

Hans-Georg Maassen told Deutschlandfunk radio on Sunday that there was an "increased abstract threat" of attacks in Germany.

Unlike Britain, Germany hasn't raised its national threat level for terrorism recently because of a lack of concrete warning signs.

Maassen says at least 400 people have left Germany to join jihadist groups in Syria and Iraq, and five have died as suicide bombers.

Maassen also wants to improve cooperation with Turkey, a key transit country for Europeans seeking to join extremist groups.