U.S. authorities investigating a tour bus crash that killed four Chinese tourists in Utah said Thursday they haven’t uncovered any mechanical problems that could explain why the driver lost control of the vehicle.
The 60-year-old driver was on his first run for a new company when the bus crashed on Sept. 20, but he knew the area from trips with another agency, according to the preliminary report from the National Transportation Safety Board.
The group of older adults from China was on a seven-day tour that started in Los Angeles and was set to end in Salt Lake City. The bus crashed near Bryce Canyon National Park.
Investigators don't know yet why the bus left the road shortly before noon. When the driver tried to correct course, the bus began to cross into an oncoming-traffic lane, so he steered sharply back to the right, the report said.
The bus rolled, hitting a guard rail, crushing the roof and throwing 11 people from the vehicle.
All 30 passengers were hurt. Four died and 15 suffered serious injuries.
The bus was equipped with seatbelts, but investigators haven't yet determined how many people were wearing them.
The Utah Highway Patrol is still investigating. Authorities have said the driver did not appear to be intoxicated.
“The big question is, why did the driver drift off the road that first time?” Sgt. Nick Street said. “It may be something simple.”