Two men are dead and two others were in hospital after a high-speed pursuit involving dozens of police cars ended with the pursued vehicle rolling into a ditch.
The pursuit began Wednesday afternoon following a smash-and-grab robbery at a jewellery store in a London mall, police said.
Four men walked into the White Oaks Shopping Centre around 1:30 p.m. and started smashing display cases with sledgehammers while telling customers to duck for cover, witnesses said.
Police arrived on the scene as the men fled in a vehicle on Highway 402.
The chase continued for 20 minutes before the suspects' vehicle lost control and rolled into a ditch.
Police said one man died at the scene, while three others were seriously injured. One of the injured men later died in hospital.
There were reports that gunshots were fired during the pursuit, but police could not confirm whether any officers discharged their weapons.
The incident is being probed by the province's Special Investigations Unit, a civilian agency that investigates incidents involving police and civilians that result in serious injury or death.