55 people suffered mostly minor injuries, though several people were taken to the hospital. All victims were ages 60 to 80.
Da Zuan is a Chinese tour bus company that often transports people to casinos.
"It's a little early to determine whether it was driver error," California Highway Patrol told reporters. "We are worried more about the injured people than the actual investigation itself."
Though it's unclear what caused the accident, one witness told KNX Newsradio that the bus swerved too far when trying to merge.
“The tires locked up and then they swerved left again, and then it swerved right, and it looked like he was gonna get on the shoulder okay, but then he over-corrected and then it went over on its faster side into the dirt,” the witness said.
“There were elderly people stuck on top of the other. They were going about 70 miles an hour and got thrown onto each other,” eyewitness Jeff Lewis said of the crash. “They were very quiet; I would say they were in shock.”
Lewis also said that he and other drivers who saw the crash got out of their cars to help pull people out of the wreckage.
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