RCMP Insp. Tim Shields said 14 people were taken to hospital following the collision early Friday morning on the Vedder Canal Bridge, 90 kilometres east of Vancouver.
He said none of the injuries was serious, although 36 passengers aboard the Greyhound were unable to get off the coach because of a damaged door.
Shields reported all the bus passengers were eventually freed and were okay, with injuries limited to bumps and bruises.
He said the crash happened at about 7:15 a.m., when some westbound drivers were distracted by smoke wafting over the bridge from the campfire below, and a chain-reaction rear-end collision resulted as some motorists hit the brakes and others could not stop in time on rain-slicked pavement.
Eastbound traffic on a parallel bridge over the Vedder Canal was halted for about an hour, while tow trucks worked to separate the mangled vehicles in the westbound lanes, in order to reopen the main link connecting the Lower Mainland with the B.C. Interior.