B.C. Emergency Health Services said two people were airlifted to hospital in serious condition and about 36 others suffered non-life-threatening injuries.
The crash happened just before 10 a.m. on the Coquihalla Highway near Brookmere, B.C., about 40 kilometres south of Merritt.
Wendy Georgenson said the tow truck was just hooking onto the car when the bus crashed into it. Several people were standing around the truck at the time, she said.
"That's where one guy broke his leg. One guy was holding his ribs and puking. They were screaming. It was mayhem," she said. "Then the bus hit the railing and it was like out of a movie. It was just horrible."
An employee at Universal Coach Line in Richmond, B.C., confirmed one of its tour buses was involved in the crash, but declined to give further information.
RCMP Cpl. Chris Newel said an investigation is in its early stages but charges are pending.
"They are gathering evidence that maybe this could have been avoided, and we will take it from there," he said.
Newel said the car's driver had called for a tow truck after crashing into a deer. The car was pulled over to the side of the highway when the truck arrived.
The truck driver was outside talking to the occupants of the car when the bus struck, he said.
Newel said the RCMP received reports that the tour guide was ejected from the bus and fell into the creek below the highway.
The guide and tow truck operator suffered serious but non-life-threatening injuries, while the car's driver and passenger were also injured, he said.
Newel said there were 30 people on the bus and many sustained minor injuries.
Interior Health said 25 people, most with non-life-threatening injuries, were admitted to hospitals in Kelowna, Kamloops and Merritt, B.C. Patients were also being accepted in Hope, B.C.
About a dozen ground ambulances and four air ambulances responded to the scene. Merritt Fire sent tents and a command vehicle.
C.J. Hodgson said she was travelling southbound at around 10:30 a.m. when she passed a tour bus with severe damage to its front end.
"The front third or so of the bus is either ripped off or smashed in. It's wide open. You can see into the bus," she said.
She said the hoods of a tow truck and a small car were smashed in and the air bags were inflated.
Hodgson said the bus appeared to have crashed into a highway railing and a handful of people were looking over it at the drop below. Another group of people were standing on the road.
"It's a big drop. If they're looking for something other than their belongings, that's scary," she said.
Drive B.C. said northbound traffic at Exit 250 reopened about eight hours after the accident, just after 6 p.m. Southbound traffic had also been reduced to a single lane earlier in the day.
Kyla Guido said she saw a tour bus with a smashed windshield and at least two passengers lying on the road when she drove by the scene earlier Saturday.
Guido said the tow truck was sideways on the highway with damage, and a small red car also appeared to have significant damage.
(The Canadian Press, CHNL, CFJC)
— By Laura Kane in Vancouver
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