British Columbia's police watchdog is investigating a collision involving an on-duty Vancouver police officer that left a pedestrian with serious injuries Saturday night.

The incident occurred at around 9:30 p.m. in the area of Knight Street and East 20th Avenue in East Vancouver.

The pedestrian was taken to hospital with serious injuries. The Vancouver Police Department said the officer was physically unharmed.

Video shows a damaged unmarked police SUV at the scene of the collision.

Investigators, however, have not said where the pedestrian was walking at the time of the incident or whether the officer involved was responding to a call.

"We will be looking at all of those factors," said Ron MacDonald of the Independent Investigations Office of B.C.

"We will look at the speed of the vehicle--how it was being driven. We'll look at the lighting conditions, we'll look at the road conditions (and) we'll look at what the pedestrian was doing."

In a statement, the IIO said its investigators were deployed to the scene shortly after the collision and are gathering evidence, interviewing civilian and police witnesses as well as reviewing any available security camera footage.

Any potential witnesses are asked to call the IIO at 1-855-446-8477.

With files from CTV Vancouver's Breanna Karstens-Smith