Mexican authorities say they have intercepted four trucks packed with nearly 800 migrants in the Gulf coast state of Veracruz.
The National Migration Institute says in a statement that the 791 people were taken to a migration facility and the drivers of the trucks were arrested.
Migrants are routinely transported through Mexico in packed semis, sometimes in dangerous conditions without food or water or sufficient fresh air.
Government video showed officials breaking the lock on the door of one cargo truck and helping migrants down.
The Saturday night statement said 1,000 immigration agents have been deployed in the north and south of Mexico. The country is under U.S. pressure to reduce the surge of mostly Central American migrants through its territory.
