Fifty four people have been confirmed killed with more than 100 injured after a truck carrying migrants, mostly from Central America, overturned in southern Mexico on Thursday, local authorities report.

The incident happened in Mexico’s Chiapas state, a border town with Guatemala, when the truck carrying dozens of migrants tried to enter Mexico, with the intention of moving on to the United States.

It is not immediately clear what caused the crash or why the victims were crammed into the truck but officials say many people who embark on the dangerous migrations from Central American countries like Honduras, Guatemala, and Nicaragua, do so because of violence, corruption, food insecurity, and a lack of economic opportunity have left many with no other choice.

The dangerous journey, often organized by people smugglers, travels north through Mexico to reach the US border, the officials say.

Mexican Foreign Minister Marcelo Ebrard, who confirmed the accident, said some of the people who died included foreign nationals.

“My condolences to the victims and affected families. In communication with the State Government and Civil Protection, we make contact with the foreign ministries of the affected countries,” Ebrard wrote on Twitter.

Mexican President Andres Manuel Lopez Obrador also shared his condolences on Twitter.

“I deeply regret the tragedy caused by the overturning of a trailer in Chiapas carrying Central American migrants,” the President said. “It’s very painful. I hug the families of the victims,” he wrote.