A statement from the National Immigration Institute said two trucks were stopped at a checkpoint before dawn in the northern state of Tamaulipas, which borders Texas.

Scanners detected people inside, and 198 migrants from Guatemala, Honduras and El Salvador were found without proper ventilation, food or water, and with practically no space to move. Photos released by the institute showed dozens of people inside a shipping container huddled in jackets and blankets.

"They were traveling in deplorable conditions," the statement said.

Three people were arrested on suspicion of human trafficking.

The migrants told authorities they began their journey in Tabasco state and traveled through Veracruz to reach Tamaulipas.

They said the highway where the vehicles were discovered between Ciudad Victoria and Linares, Nuevo Leon state, has been identified by human smugglers as a way to avoid controls on the road from Veracruz to the border city of Reynosa, Tamaulipas, across from McAllen, Texas

A separate statement described a similar discovery Friday afternoon in the Gulf coast state of Veracruz, saying a truck was found carrying 102 Central Americans who "displayed signs of dehydration and suffocation" and whose lives were at risk.

Dozens of children were among the migrants in the trucks.

Also Saturday, Mexico's Navy reported that the coast guard rescued seven Cubans from a makeshift raft that was adrift Friday about 150 miles (240 kilometers) northeast of the Yucatan Peninsula.