In this Saturday, July 12, 2014, photo, a migrants walk bewtween trains after getting off one during their journey toward the U.S.-Mexico border, in Ixtepec, southern Mexico. The migrants pay thousands of dollars per person for the illegal journey across thousands of miles in the care of smuggling networks that in turn pay off government officials, gangs operating on trains and drug cartels controlling the routes north. (AP Photo/Eduardo Verdugo)