Kurdish forces who have been fighting the "Islamic State of Iraq and Syria" (ISIS) in Syria with backing from the international coalition say they hold around 900 of the group's foreign fighters from 44 countries, AFP reported Monday (October 22nd).

According to Kurdish foreign affairs official Abdel Karim Omar, Syrian Kurds also hold 550 women and around 1,200 children from the families of ISIS members.

Alleged fighters are usually detained in jail, while women and children are held separately in camps.

Many of the detainees do not have identity papers, Omar said.

"Some of the women have four children, each from a different father and each father from a different country," he said.

The Kurdish authorities in northeastern Syria have repeatedly said they will not try any foreign fighters.

"We try the local Syrian ISIS mercenaries, but we will not try the foreigners," Omar said.

"There are too many of them. It is a heavy burden we cannot carry on our own," he said.

The Kurds were trying to exert "pressure on the international community and countries that have nationals in our region," Omar said.

"We are trying by all means for those countries to take back their nationals."