The U.S. military has ordered its nearly 3,500 troops stationed in Iraq to reacquaint themselves with their chemical weapons suits due to evidence that the Islamic State has obtained chemical weapons and used them on multiple occasions.

“It is a precautionary measure,” a defense official told Fox News, acknowledging the order.

During a briefing Thursday, the Pentagon would not publicly confirm the order but reassured reporters that the military is prepared to handle a chemical attack by ISIS. […]