Police credited a safety bumper with saving the lives of two women who sustained undetermined injuries during a collision on the Trans-Canada Highway, west of St. John's. (CBC)

Police in eastern Newfoundland said Monday two women were lucky to have survived a collision on the Trans-Canada Highway involving a stalled tractor-trailer.

RCMP said a car collided with the rear end of a tractor trailer that had already broken down in the eastbound lane of the TCH, between the Holyrood Access Road and Salmonier Line.

Two people were sent to hospital with unknown injuries, police said, although neither's life was at stake.

RCMP said the driver of the truck had properly put warning markers around his rig. The collision occurred about an hour after the truck broke down.

Const. Harry Mouland said a safety device that the driver had installed under the rear of the trailer limited the damage.

"The fact that the truck had the safety bumper on the back, it kind of saved the lives with the ladies — it saved them from going up and under the trailer," Mouland said.

"It could have been a lot worse. If the truck and the trailer didn't have the safety bumper, the way it should be as per law in Newfoundland and Labrador, we would have definitely had a fatality here this morning," Mouland said.

Mouland said witnesses at the scene reported that the sun was low in the sky and had been very bright at the time of the collision. He said under such conditions, drivers may think that a truck is moving, when it is not.

Police said it would take several hours to clear the scene. During that time, eastbound traffic has been reduced to one lane in the area.