At least 820 Islamists have left Germany to join Islamist militants in Syria and Iraq, the German domestic security agency said Friday, voicing concerns about the rapid radicalisation of minors after two recent attacks.
Around 40 of those who have travelled to the conflict-torn countries are aged under 18, and half of these are girls, according to latest data released by the BfV spy agency.
"Young people are being radicalised quickly and permanently," said its chief Hans-Georg Maassen.
"It is particularly problematic that they cultivate a readiness and ability to heed the call of the IS (Islamic State) to murder non-believers in their own country, using whatever means at their disposal," he said, referring to two recent attacks in Germany.
Police in April arrested two 16-year-olds over an explosion that wounded three people at a Sikh temple, in what was believed to be an Islamist motivated attack against an Indian wedding party at a temple in the western city of Essen.
In the other attack, a 15-year-old girl stabbed a policeman in the neck in Hanover in February. German prosecutors said she was carrying out an operation for the Islamic State militant group.
The BfV has sought authorisation to collect and store personal data about under-16s who are suspected of extremism.
Among the 820 who have left Germany, about a third have returned while about 140 have been killed in Syria or Iraq.
The intelligence agency last September said 740 Islamists had travelled to the conflict zones.