More than 3,500 U.S. troops have been deployed near three areas along the U.S.-Mexican border where U.S. officials have assessed migrants and asylum seekers from Central America are most likely to try to enter the country in coming weeks.

Troops are in place around McAllen and Brownsville, in Texas’ Rio Grande Valley; San Ysidro, Calif., south of San Diego; and Nogales, Ariz., U.S. officials said.

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