CAMP PENDLETON, Calif. (AP) — Another 130 U.S. troops have arrived in Iraq on what the Pentagon describes as a temporary mission to assess the scope of the humanitarian crisis facing thousands of displaced Iraqi civilians threatened by militants from the group Islamic State.

Defense Secretary Chuck Hagel says, "This is not a combat boots on the ground kind of operation."

Instead, Hagel calls the 130 troops "assessors."

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