Almost 100 migrants were left abandoned in a freight trailer on a highway in Mexico and had to break their way out to escape suffocation, Mexican authorities said Thursday.

The 94 undocumented foreigners, including several children, from Guatemala, Honduras and El Salvador were turned over to immigration authorities, according to Mexican officials. Around 100 more were believed to have fled.

The migrants were bound for the US border and were discovered on Wednesday night on a highway in the eastern state of Veracruz.

"They indicated that they were abandoned by the driver," a police report said.

Locals help break open container

The abandoned migrants had to break holes in the freight container to get out, according to Carlos Enrique Escalante, the head of the state migrant attention office.

Some of them sustained injuries when they had to jump off the roof of the trailer. The injuries were not considered life-threatening. About a dozen people were reportedly taken to hospital due to bruises and symptoms of asphyxiation.

Residents near the town of Acayucan helped break open the freight container, Escalante said.

Migrants die or disappear en route to US

People smugglers in Mexico often use overcrowded trucks to illegally transport migrants across the border.

In June, more than 50 migrants, including 22 from Mexico, died after they were abandoned in the sweltering heat in a semi-trailer in San Antonio, Texas.

In a statement, the White House had called the immigrant deaths "absolutely horrific and heartbreaking."

Around 6,430 migrants have died or disappeared on their way to the US since 2014, according to the International Organization for Migration (IOM).