A commercial passenger bus driving through Mississippi on its way to Mexico ran off a highway and overturned early Saturday, killing seven people and injuring dozens. The accident occurred on Interstate 20 east of Vicksburg, CNN reports. A total of 37 people were taken to hospitals in Vicksburg and Jackson, the Mississippi Highway Patrol said. A 6-year-old boy and his 16-year-old sister were among those killed, per the AP. “Anytime you have people injured or killed, it’s tragic, but when you have a situation like this where you have multiple fatalities and multiple injuries, it makes it even worse,” said Warren County Sheriff Martin Pace.

The bus, a 2018 Volvo, is owned by Autobuses Regiomontanos, which transports passengers between Mexico and the US, a company spokesperson said. The company is based in Monterrey, Mexico, Miranda Fernandez said. Its website lists several US locations; it’s not clear where the trip had originated. “All of the passengers go through proper immigration checkpoints and must show their passports or visas to enter either Mexico or the United States,” Fernandez told CNN. (More bus accident stories.)