Some people were ejected from the bus; others were trapped inside after the collision that took place last night. It was difficult for rescue workers to immediately identify exactly how many people were killed, Los Angeles Times reported.
The paper quoted California Highway Patrol spokesman Mario Lopez as saying that all of the known fatalities appeared to come from the bus, which was a charter carrying 38 passengers, including children.
The sedan was carrying three people, and the truck had one occupant, officials said.
An official said the bus lost control while going down the mountain and rolled over the truck at least once.
"It happened so fast, I don't know how it all happened," one passenger told the San Bernardino Sun. "This was supposed to be a good day out with my companions and then this happened."
It took firefighters more than two hours to extricate all the injured. In all, 27 were taken to area hospitals, at least six of them in critical condition. Some of the injured were children, the paper said.
"Investigation into the cause hasn't even begun because patient treatment and transport takes priority," said Eric Sherwin, a spokesman for the San Bernardino County Fire Department.
A spokesman for Loma Linda University Medical Center, Herbert Atienza, said the hospital received four crash victims
