Mexican authorities rescued nearly 100 migrants who escaped from a stifling trailer being driven by a people smuggler in the coastal state of Veracruz, officials said on Thursday.

About 400 migrants were being transported in the trailer, near the small town of Acayucan, when they began to suffocate, authorities in the area told Reuters.

"They broke through the roof of the trailer because they were suffocating and since there was a gas station nearby, the employees there helped them escape," said Jose Dominguez, director of civil protection in nearby Oluta.

"Most of them jumped off," paramedic Cristobal Cisneros said, adding that many had been treated for ankle or knee fractures.

Dominguez said a 911 call came in at around 9:20 p.m. on Wednesday and a total of 94 migrants were found after a search of the truck and nearby brush where some had tried to hide.

Thirty-two of those found were from Guatemala, while five Hondurans, four Ecuadorians, two Indians, one Salvadoran and one Nepali were among those on the trailer, Dominguez said, adding that the rest were not identified because they had "left" the scene.

Guatemala's foreign ministry issued a different number on Thursday, saying 89 of the rescued migrants were Guatemalan, 55 adults and the rest minors.

According to paramedic Kenya Diaz, some migrants sought help, while others decided to run away, making identification difficult.

One official who declined to be identified told Reuters he believed the smuggler transporting the migrants was inexperienced because the trailer was abandoned before a toll booth where trailers are inspected.

The rescue follows a series of deadly incidents involving migrants in Mexico and the United States.

Last month, 53 migrants died in San Antonio, Texas, after being packed into a sweltering tractor-trailer.

Some people have died along the border, some jumping from the wall that separates Mexico and the United States. Deaths on the border broke records last year, and are on track to be as bad or worse in 2022, according to the United Nations.

Mexico's migration institute and the national guard, both of which responded to the scene, did immediately respond to requests for comment.