Sarnia police attended the scene of a vehicle collision at the intersection of George Street and Christina Street North Wednesday morning.
According to police, a 69-year-old male pedestrian was struck near the intersection by a pickup truck.
He was transported by Lambton EMS to hospital with life-threatening injuries.
The male driver of the pickup truck was uninjured.
The intersection was closed for a period of time but has since been re-opened.
Police continue to investigate the incident and further updates will be provided as they become available.