Migrant couple from El Salvador, Rene, 20, left, and Brenda, 20, who is five-months pregnant, pose for a photo inside a migrant shelter in Ixtepec in the state of Oaxaca in southern Mexico, Tuesday, April 30, 2013. Migrants crossing Mexico to get to the U.S. have increasingly become targets of criminal gangs who kidnap them to obtain ransom money. (AP Photo/Eduardo Verdugo)