Mexican officials on Sunday were attempting to return almost 200 Central American migrants to their home countries after they escaped an abandoned trailer.

The migrants were found Saturday in a trailer in Veracruz state, about 400 miles from the U.S. border, Mexico's National Institute of Migration said. The rescue came a week after 10 undocumented immigrants died in a packed, overheated trailer in San Antonio, Texas.

Officials told AFP news service the 178 occupants of the truck Saturday apparently realized they had been abandoned by the traffickers and a few escaped, seeking help from local residents who provided food and water.

The Central Americans were shuttled to a migration center for medical assistance before the process began to return them to their home countries, the migration agency said.

No arrests were immediately reported. In the San Antonio case, a Florida trucker is facing charges that could bring the death penalty. James Mathew Bradley Jr., 60, told police he was unaware of the human cargo packed in his rig.

But one passenger told authorities about 100 people stuffed in the trailer Bradley was hauling took turns breathing through a hole in the wall. More than two dozen survivors were rushed to hospitals, some in critical condition.

Homeland Security Secretary John Kelly — who is leaving the post to serve as chief of staff to President Trump — said the Texas tragedy demonstrated the "brutality" of the human smuggling rings.

"These smugglers have no regard for human life and seek only profits," Kelly said.

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