ISIS reportedly fired a chemical weapon, a mustard agent, into Qayarrah air base in Iraq, just south of Mosul on Tuesday, which is where both U.S. and Iraqi troops are operating out of, multiple U.S. officials told CNN.
No one was injured or harmed after the shell landed inside the base. They tested the chemical and based on the initial reading, they believe it to be a mustard agent. The second test came out negative, but was sent to the lab to be examined further.
According to the officials, the mustard agent was “ineffective” and “poorly weaponized.”
To play it safe, U.S. troops went through decontamination showers, even though no one showed symptoms of exposure. There are hundreds of U.S. troops staged at the base to support Iraqi forces.
It is suspected by the Pentagon that ISIS is responsible for creating the mustard agent since they have used it in the past. Officials said that they expected ISIS might try using chemical agents as U.S. and Iraqi forces advance towards the ISIS stronghold of Mosul.
During the campaign against ISIS, U.S. airstrikes have struck several mustard agent production sites. They continue to do so when they are found.