The Islamic State (IS) has killed three Chinese militants who tried to leave the group, an official from the Kurdish security force in Iraq told the Global Times.

The Kurdish security official  said Wednesday that in the past six months, IS has executed 120 of its members who attempted to escape from the group and leave Iraq and Syria. Among the 120, three were Chinese citizens and were members of the East Turkestan Islamic Movement (ETIM), a terrorist organization that is also known as the Turkistan Islamic Party.

One of the Chinese militants was seized and executed last September, according to the official. He became disillusioned with IS after arriving in Syria, but was later caught and executed after an unsuccessful attempt to flee to Turkey.

The official said the other two Chinese militants were executed last December in Iraq along with 11 other IS members from six countries. They were executed for "treason."

Foreign ministry spokesperson Hong Lei on Thursday said China opposes all forms of terrorism, and is willing to cooperate with the international community in fighting terrorist forces, including the ETIM, to safeguard global security.

Singapore-based Chinese news portal zaobao.com earlier reported that around 300 Chinese extremists were fighting for IS in Syria and Iraq after travelling to the two countries via Malaysia.