(YUCAIPA, Calif.) -- At least eight people were killed and 38 others were injured when a tour bus collided with two other vehicles in Southern California Sunday night.
The accident happened around 6:30 p.m. on State Route 38 near Yucaipa. According to officials, the bus, which was carrying a tour group from Tijuana, Mexico, hit a sedan, flipped over and then hit a pick-up truck.
"The bus is overturned. There's significant damage to the passenger side of the bus. And obviously quite a bit of debris is kind of thrown and spread out all over the place," said Ronald Walls, a battalion chief for the San Bernardino County Fire Department.
ABC News affiliate KABC-TV in Los Angeles reported at least 17 people were critically injured.
"Some of the victims have been thrown from the vehicle as well. When it rolled, several of them were ejected from the vehicle as well," Walls said.
It is not yet clear what caused the crash.
"We're talking to witnesses, we're talking to the parties involved. There's a possibility of mechanical issues with the bus. And that's what our multi-disciplinary action team is doing right now at the scene," said Officer Mario Lopez of the California Highway Patrol.
The National Transportation Safety Board announced on Monday it was also launching a team to investigate the incident.
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