Sept. 1 (UPI) — The National Transportation Safety Board is on the scene investigating a bus crash on Interstate 20 in Mississippi on Saturday that killed seven people and left dozens more injured, the Mississippi Highway Patrol said Sunday.

The commercial bus, a 2018 Volvo, was traveling westbound on Interstate 20 near Bovina in Warren County early Saturday morning when it left the roadway and overturned, according to the Mississippi Highway Patrol.

Officials said the crash occurred east of Vicksburg, Mississippi, and left 37 people injured, officials said.

The NTSB has said the condition of the tires are likely to have caused the crash.

“The NTSB, in coordination with the Mississippi Highway Patrol, is sending a go-team to conduct a safety investigation into Saturday’s crash involving a motor coach roadway departure and roll-over after experiencing a tire failure while on Interstate 20 near Vicksburg, Mississippi,” the NTSB said in a statement posted on X.

Six people onboard the bus, including a 6-year-old boy and his 16-year-old sister, were pronounced dead on the scene. Another person died at the hospital.

The bus was traveling from Atlanta to Dallas with 41 passengers and two drivers, the highway patrol said.

The bus was operated by Autobuses Regiomontanos with offices in Laredo, Texas. The company bills itself as having 20 years of experience providing cross-border trips between 100 destinations in Mexico and the U.S.

Its website promotes “a modern fleet of buses that receive daily maintenance,” and offers “trips with a special price for workers.”

Warren County Coroner Doug L. Huskey told ABC News on Sunday that all of the people killed in the incident were from Mexico