Mỹ tìm cách ngăn chặn di dân lậu từ Trung Đông

JUCHITAN, MEXICO - AUGUST 06: Central American immigrants ride north on top of a freight train on August 6, 2013 near Juchitan, Mexico. Thousands of Central American migrants ride the trains, known as 'la bestia', or the beast, during their long and perilous journey through Mexico to reach the U.S. border. Some of the immigrants are robbed and assaulted by gangs who control the train tops, while others fall asleep and tumble down, losing limbs or perishing under the wheels of the trains. Only a fraction of the immigrants who start the journey in Central America will traverse Mexico completely unscathed - and all this before illegally entering the United States and facing the considerable U.S. border security apparatus designed to track, detain and deport them. (Photo by John Moore/Getty Images)