Police say they are searching for the driver of a vehicle involved in a downtown hit-and-run that left a 52-year-old pedestrian with life-threatening injuries.

The incident occurred in the area of Dundas and Parliament streets shortly before 3 a.m.

According to investigators, a 52-year-old man was crossing Dundas Street with a group when he was struck by an eastbound vehicle that had crossed into the westbound lanes.

The victim, police say, was transported to hospital in critical condition.

The vehicle, identified by police as a grey Honda Civic, was last seen fleeing the area eastbound on Dundas Street.

Police are asking witnesses and members of the public with security footage or dash camera video to reach out to investigators.