Reuters: Iraqi Kurdish authorities said on Saturday they had evidence that Islamic State had used chlorine gas as a chemical weapon against their peshmerga fighters in northern Iraq in January.

The Security Council of the semi-autonomous Kurdish region said in a statement to Reuters that the peshmerga had taken soil and clothing samples after an Islamic State car bombing attempt on Jan. 23.

It said laboratory analysis showed “the samples contained levels of chlorine that suggested the substance was used in weaponized form.” The Kurdish allegation could not be independently confirmed.