Twelve residents of the war-torn Iraqi city of Mosul were treated for injuries from a suspected chemical attack this week, an official with the International Committee of the Red Cross said.
The patients, who are being treated in hospital in nearby Irbil, are "showing clinical symptoms consistent with an exposure to a blistering chemical agent," said Robert Mardini, the organization's regional director for the Middle East.
The five children, three women and four men have symptoms that include blisters, coughing, redness in the eyes, irritation, and vomiting.
US volunteers aid Mosul's wounded at frontline clinic
"The use of chemical weapons is absolutely prohibited under international humanitarian law. We are deeply alarmed by what our colleagues have seen, and we strongly condemn any use of chemical weapons, by any party, anywhere," ICRC's Mardini said.
The Organization for the Prohibition of Chemical Weapons released a similar statement on Sunday, stating that it's "seriously concerned" over the alleged use of chemical weapons in Mosul.
"Parties to the Chemical Weapons Convention deem the use of chemical weapons by anyone under any circumstances as reprehensible and wholly contrary to the legal norms established by the international community," the organization said.
Dr. Lawan Miwan, head of Emergency Hospital in Irbil, told in a statement his hospital is treating two cases with symptoms consistent with exposure to a toxic chemical agent.
CNN talked with two residents of east Mosul who reported smelling "something strange," "like a chemical agent," or "mustard gas" following mortar attacks on eastern Mosul on Wednesday and Thursday. The residents said the attacks came across the Tigris River from western Mosul.
ICRC spokeswoman Sara Alzawqari said the first three cases were brought to the hospital on Wednesday, followed by another four Thursday. Five victims arrived in somewhat better medical condition on Friday. All are victims of the same attack, Alzawqari said.
The World Health Organization has responded to the reported use of chemical weapons agents in eastern Mosul, activating an emergency response plan to treat those who may be exposed to the highly toxic chemicals, the WHO said Friday.
Two Iraqi security officials near Mosul could not confirm nor deny the incidents .
ISIS has used chemical weapons on numerous occasions in Iraq and Syria, including in the battlefield in northern Iraq, according to Iraqi and US officials.
This is believed to be the first such attack in Mosul since the October start of the offensive to retake Iraq's second most populous city from ISIS control .