An elderly woman was killed and another was seriously injured when their car was T-boned by a dump truck in south Ottawa Wednesday morning.

Police say a car driven by one of the women was struck at the intersection of Bank Street and Rideau Road at about 10:30 a.m.

"The vehicle in question wanted to turn left and the view was blocked. Unfortunately, they made the left-hand turn thinking it was clear and there was another dump truck coming the other way and the vehicle got T-boned," said Ottawa police Sgt. Mark Gatien.

The 84-year-old passenger of the car was pronounced dead at the scene. The driver of the car, also an elderly woman, was extricated from the vehicle and rushed to hospital in serious condition.

Firefighters say both women were trapped in the car and the jaws of life had to be used to get them out.

Police say the driver of the dump truck did nothing wrong: he was in his lane and was driving the speed limit. He was not injured.

"I'm sure he's shaken up. Unfortunately, in this situation you have to understand there's nothing you could have done about it. It's a crappy thing to go through," said Gatien.

Police are now looking for the driver of a commercial dump truck who may have witnessed the fatal crash.

Police say a faded yellow commercial vehicle was heading south on Bank Street, in the turning lane near Rideau Road, at about the same time the car and dump truck collided.

The driver is not believed to be involved in the crash, but police think he or she may be an eye-witness. That driver is asked to contact Ottawa police at 613-236-1222, ext. 2475.

With a report from CTV Ottawa's Kate Eggins