Defense secretary’s order doesn’t specify how many will be sent

Defense Secretary Jim Mattis on Friday approved a request from the Department of Homeland Security to provide additional U.S. troops on the U.S.-Mexcio border, according to officials familiar with the plan. The Pentagon support under Mr. Mattis’s directive begins Tuesday and ends Dec. 15, a U.S. official and an administration official said. The order doesn’t specify how many troops would be assigned to the border. Rather, it directs the Pentagon to determine the military personnel that is needed and how to fill the request, the U.S. official said. The troops deployed are expected to come from active duty units, the U.S. official said, not National Guard. The Pentagon expects to announce which troops would be deployed in the next two days, the U.S. official said.

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