UNITED STATES—Human Rights Watch has called the recent ISIS chemical attacks a “war crime” after the militant group carried out at least four attacks in the past few months that have left individuals severely burned and injured.

“The use of toxic chemicals as a means of warfare is a serious threat to civilians and combatants in and around the embattled city of Mosul and is a war crime,” stated the Human Rights Watch organization. On Friday, November 11, HRW reported what they believe is the fourth chemical attack from ISIS on Qayyarah, a town that is 60 km south of Mosul. A few weeks ago a rocket was fired and landed in the garden of a home. According to Reuters.com, a five-year-old girl named Doaa was playing in the courtyard of her home next door at the time when the projectile exploded and emitted a “toxic gas.”  Doaa was later in extreme pain and her skin has now hardened and blackened.

Recent attacks have been reported including a chemical attack at a cafe and refinery in Qayyarah. After interviewing victims and doctors, HRW gathered information on the chemicals used in the past attacks, one being Sulfur Mustard, a blister agent, that is believed to have been in the projectile. According to HRW, the use of any blister agents or toxic chemicals to do harm would violate a 1933 Chemical Weapons Convention that Iraq joined in 2009.

The attacks began after Iraqi forces, backed by the U.S., retook the town of Qayyarah in late August.