A total of 55 people were injured when a charter bus bound for a casino overturned on the 210 Freeway in Irwindale on Thursday, snarling traffic as emergency crews responded with helicopters and an army of ambulances.
The 10 a.m. crash stopped all traffic on the eastbound lanes just past the 605 Freeway interchange. Authorities said it was too early to tell how it happened.
Witnesses said they saw the bus brake hard in the far left lane before it ended up on its side on the freeway's shoulder several lanes to the right. Aerial TV news footage showed skid marks streaking across the freeway behind the crash site.
Jeff Lewis, a truck driver and former firefighter in the military, said he was driving behind the bus when it slammed on the brakes.
Seconds later, with the bus resting on its side, Lewis said he and five or six others got out of their cars and helped pop open the front window to help passengers climb out one-by-one.
The group pulled about half the passengers out in about 15 minutes, he 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," Lewis, 49, said. "They were very quiet; I would say they were in shock."
At one point, the entire freeway was closed in both directions as emergency crews triaged the injured, according to authorities. Seven people were taken by helicopter to local hospitals, although most injuries were described as minor to moderate.
A receptionist at the Monterey Park-based charter company Da Zhen Bus confirmed that the bus was heading to the San Manuel Indian Bingo and Casino in Highland after picking up passengers in Monterey Park and San Gabriel.
The owner of the company was unavailable for comment, the receptionist said.
The westbound lanes of the freeway -- closed to allow helicopters to land -- were reopened about 11 a.m., but at least two eastbound lanes remained closed as crews continued to investigate and clean up the crash site.