The California Highway Patrol said the accident occurred early Monday in the city's Southland area when the bus tried to exit the expressway and approached the ramp too fast, crashing through a fence. Its door was blocked, locking in 38 passengers and the driver, KCBS-TV reported.
"The bus tried to get on the ramp to exit, but he [came] too fast. He can't control the bus," passenger Eduardo Magana said.
The Los Angeles County Fire Department said 13 people were injured, 11 sustaining minor injuries and two suffering moderate injuries. They were taken to area hospitals.
"The fire department had to break the glass and escort the passengers out of the door through the glass opening," highway patrol Sgt. Grady Stevens said.
The bus is operated by Travel Tours Americas International, KCBS said. It was traveling from the Fantasy Springs Resort Casino in Indio to Eagle Rock and Panorama City in Los Angeles, officials said.
Law enforcement officials said they haven't determined the official cause of the crash or why the driver lost control.
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