Seven Mexican travelers were killed and dozens of other people injured early Saturday when a commercial passenger bus headed for Mexico experienced tire failure and rolled over off a highway east of Vicksburg, Mississippi, officials said.

The National Transportation Safety Board will consider several factors in its investigation into the crash on Interstate 20, including motor carrier safety and tire maintenance, NTSB member Todd Inman said Saturday in a news conference.

All those who died were Mexican, the nation’s Foreign Affairs Secretary Alicia Bárcena said late Sunday on X. Among them were siblings, ages 6 and 16, Warren County Coroner Doug Huskey said. Thirty-seven passengers were taken to hospitals in Vicksburg and Jackson with injuries, the Mississippi Highway Patrol said.

The 2018 Volvo bus overturned in the westbound lanes near Bovina, the highway patrol said. It had originated in Atlanta and was next headed to Dallas, according to Inman.

“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,” Warren County Sheriff Martin Pace told CNN affiliate WAPT.

The bus belongs to Autobuses Regiomontanos, which transports passengers between Mexico and the United States, according to Miranda Fernandez, a company spokesperson. The company is based in Monterrey, Mexico, Fernandez said, and has several locations in the United States, according to its website.

“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.

“Several Mexican identification documents” were found on the bus, according to Mississippi Highway Patrol spokesperson Kervin Stewart.

Six passengers were pronounced dead at the scene, while the seventh died at a hospital, according to the highway patrol.

The bus ended up in a ditch and many passengers were ejected, tow truck driver Keith Allison told WAPT.

This story has been updated with additional information.

For more info, visit http://www.CNN.com