A pedestrian is in hospital after being hit by a car in the westbound collector lanes of Highway 401 near the exit to northbound Highway 400.
It happened around the noon hour on Friday.
A car was stopped in the right lane attempting to make an exit to the 400, police say, when several vehicles swerved around the car before it was hit by another vehicle.
When the occupants of the first vehicle got out to inspect the damage, one person was struck by another oncoming vehicle.
The OPP says the injuries are serious but not life-threatening.
All westbound collector lanes of the 401 at the 400 are closed for the investigation.