Hans-Georg Maasen, the President of the Germany Federal Office for the Protection of the Constitution, in an interview with the German Focus weekly news magazine said that more than 20 German nationals who joined the militants operating in Syrian had been killed.

Maasen said that most of the German nationals belong to Salafi extremist groups, saying the number of the extremists in Germany exceeded 6 thousand.

Maasen also warned that the extremists would pose a great threat to Germany on their return. Maasen underscored that some of the extremists received military and terrorist trainings and were prepared to carry out violent operations.

The war in Syria started in March 2011, when pro-reform protests turned into a massive insurgency following the intervention of Western and regional states.

The unrest took in terrorist groups from across Europe, the Middle East and North Africa and turned into one of the bloodiest conflicts in recent history.

RA/NJF