ISIS executes 100 foreign-born fighters trying to leave Syria

London (AFP) - The Islamic State extremist group has executed 100 of its own foreign fighters who tried to flee their headquarters in the Syrian city of Raqqa, the Financial Times newspaper said Saturday.

IS fighters in Raqqa said the group has created a military police to clamp down on foreign fighters who do not report for duty. Dozens of homes have been raided and many jihadists have been arrested, the FT reported.

Some jihadists have become disillusioned with the realities of fighting in Syria, reports have said.

According to the British press in October, five Britons, three French, two Germans and two Belgians wanted to return home after complaining that they ended up fighting against other rebel groups rather than Assad's regime. They were being held prisoner by IS.

In total, between 30 and 50 Britons want to return but fear they face jail, according to researchers at the International Centre for the Study of Radicalisation at King's College London, which had been contacted by one of the jihadists speaking on their behalf.