A man has been seriously injured after being struck by a vehicle on Highway 400 just after midnight near King City.

OPP say a car pulled over on the side of the highway near King Road at around 12:30 a.m. on Saturday. A 22-year-old male passenger got out of the vehicle and was hit by a car.

The pedestrian was taken to hospital with serious injuries. The driver of the vehicle did stay at the scene.

The collision closed the northbound lanes of the highway for several hours, forcing OPP to divert thousands of motorists. It has since reopened.

No charges have been laid and the investigation is ongoing.