More details are coming to light about a horrific tour bus crash on a major B.C. highway, as investigators continue to sift through the debris of an accident that left dozens of people injured.

On Friday, Mounties said video footage obtained from a dashboard camera has helped them rule out speed as a potential factor in the crash, but they have yet to determine a cause.

Investigators say the bus hit a median while travelling southbound before it skidded across several lanes of traffic, then rolled into a ditch as several passengers were ejected from the vehicle.

"It's more an issue that the driver drove into the centre median  and then veered too hard trying to get onto the road," Sgt. Brian Nightingale said. "We're doing mechanical (inspections) today on the bus, so that  will rule out any kind of mechanical factors, like steering and  braking and that kind of stuff."

Health officials have raised the number of patients listed as critically injured from five to seven, and said six people remain in serious condition. In total, 24 people remain in hospital.

Several of the people injured are confirmed to be children.

The bus was being used by Richmond-based company Super Vacation Canada for a tour in the Rocky Mountains. It was chartered through another company, Western Bus Lines, based in Kelowna.

In a press conference Friday, Super Vacation vouched for the bus line and the driver who was operating the bus.

“I would like to emphasize, this is one of the major, mainstream bus companies,” Super Vacation spokesman Nicholas Kam said. “It’s huge, it’s very famous over 35 years.”

Kam said the bus was carrying tourists from all around the world, including parts of Asia and the United States.

Police confirmed all 56 passengers were injured, five critically, when it crashed 20 kilometres southwest of Merritt at around 2:30 p.m.

Five air ambulances flew the most critically injured to Royal Inland Hospital in Kamloops, while others were flown to Kelowna General Hospital.

Forty-three of the injured are being cared for in Interior Health facilities while 12 were transported to Lower Mainland hospitals, according to Interior Health spokesperson Michaela Swan.

The condition of the driver is currently unknown.

One witness told CTV Vancouver the bus was speeding on a dangerous downhill section of the highway.

“We were doing 130. That’s when the bus passed us. My boyfriend is in the Canadian Forces and he said that bus is driving too fast with that many passengers, especially downhill where all trucks are going really slow,” said Kat Woycechowsky, who was driving on the Coquihalla at the same time as the bus.

Traffic investigators confirm that road conditions were bare and dry, and visibility was clear at the time of the crash. A mechanical inspection is underway.

Highway 5 reopened Friday morning in both directions after shutting down following the crash.

Super Vacation Canada said it has sent staff to Kamloops to help reconnect families and to touch base with customers.

The company said it will send a charter to the area to pick up passengers who have been medically cleared, and take them back to Vancouver.

With files from The Canadian Press