Teen thrown to her death in bus crash in Alberta, British Columbia

A 14-year-old boy, who was also tossed from the bus and landed beneath the trailer of the gravel truck, was taken to hospital in Edmonton where he was listed in critical but stable condition.

Miraculously, none of the other dozen or so elementary to high-school aged children on the bus nor the drivers and passengers in the three vehicles involved suffered serious injuries.

Mounties are still trying to piece together what happened on Highway 53 just outside Rimbey, a community of 2,252 people about 130 kilometres southwest of Edmonton.

RCMP Sergeant Patrick Webb said the bus had stopped in the westbound lane on a straightaway portion of highway to pick up the children. An SUV, driven by a woman who had two young children strapped in car seats behind her, was stopped behind the bus as she watched students board.

A gravel truck that was also travelling westbound slammed into the SUV, propelling it into the ditch. The truck then collided with the back of the bus.

"The guy in the gravel truck, he tried to swerve and tried his best he said, and he was all upset," Ms. Anderson recalled.

All three vehicles suffered heavy damage. The back of the bus was sheared off. Debris from the crash was scattered on the roadway.