U.S. authorities threw tear gas at a group of Central American migrants who attempted to push past Mexican police and border fences to illegally cross into the U.S. Authorities temporarily shut down the San Ysidro border crossing between Tijuana and San Diego after a group of a few hundred migrants -- many with children -- protesting the slow pace of asylum request processing tried to rush the fence between the two countries. Some migrants believed that they would be granted asylum if they managed to reach U.S. soil, reports