At least 49 people being transported in a cargo truck were killed on Thursday in southern Mexico when the vehicle rolled over and crashed into a pedestrian bridge.

The crash took place in the state of Chiapas, and left 58 people injured. The passengers appeared to be migrants from Central America, The Associated Press reports. Luis Manuel Moreno, the head of the Chiapas state civil defense office, told reporters that some of the survivors said they were from Guatemala. One man who survived the crash, Celso Pacheco, told AP he estimates about 10 young children were on board.

Pacheco said it felt like the truck, heavy with so many people, was speeding before the crash. He told AP he was trying to reach the United States, but expects to be deported back to Guatemala. It is unclear if the driver survived the accident.

Several rescue workers told AP that several migrants fled the scene because they did not want to be detained by immigration officials. Mexico’s National Immigration Institute said the survivors will be offered humanitarian visas, and the country will cover the funeral costs for victims. Mexican President Andrés Manuel López Obrador called the deaths “very painful.”