ERBIL, Kurdistan Region – A Kurdish military expert said on Monday that the Islamic State group (ISIS) has transferred mustard gas and other chemical weapons from Syria in a bid to use it against the Kurdistan Region’s Peshmerga forces.

“ISIS has seized chemical weapons including the mustard and toxic gas in Syria and they transferred them to their controlled areas in Iraq, where they are in close proximity to Peshmerga frontlines, especially in the group’s stronghold of Mosul, to use them in fights against the Peshmerga,” Ahmed Shawqi, a Kurdish military expert, told Rudaw.

He believes that “due to failures against the Peshmerga, ISIS has turned to using chemical weapons to advance into Peshmerga territories, but they have never been successful in doing so.”

Internationally, such weapons are prohibited. But "they (ISIS) never respect the international norms and laws," Shawqi said.

After a suspected chemical weapons attack by ISIS on the Peshmerga earlier this month, tests proved that ISIS had used mustard gas against the Kurdish forces on the Gwer- Makhmour front, wounding several Peshmerga soldiers.

Brigadier General Sirwan Barzani, commanding officer of the infantry division in the area, said Friday that the mustard gas had come in a mortar barrage of a kind the Kurds had not seen before in ISIS attacks.

US officials had announced an investigation into whether ISIS had used chemical weapons against Kurdish forces after a report was broadcast by Rudaw TV and the ENEX media network.

Mustard gas, or sulfur mustard, has been classified as a chemical warfare agent by the Centers for Disease Control and Prevention. The gas was invented and gained infamy in World War I and was prohibited by international treaty in 1993.

Rudaw