BARBARA STARR: The most important thing, no U.S. troops hurt in this but some did go through decontamination as a precaution. It happened on Tuesday, but now as we speak, this chemical shell is being tested by the U.S. military to see exactly what was in it. The shell landed on an air base in northern Iraq where U.S. and Iraqi troops are operating, getting ready to try and fight to take Mosul back from ISIS. The shell landed, U.S. troops went out to look at the shell. They saw something suspicious. They tested it and the test came back positive for mustard agent. They are testing it further. Why do they believe it’s ISIS? ISIS is up in that area and they’re desperate to hold on to Mosul. They wanted to prove to the world that they have in their view, a caliphate, an Islamic state. ISIS has used this type of mustard agent before against civilians. A lot of concern about what is happening here. U.S. troops do have and have had protective gear against this type of attack. And again, the most important thing, Jake, no U.S. troops exhibiting signs of exposure to the agent. Even as the U.S. tries to figure out exactly what did transpire here.
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