Two major crashes have forced the closure of Highway 401 eastbound between Lansdowne and Mallorytown during a powerful snowstorm that has made roads across eastern Ontario hazardous.

Ontario Provincial Police say multiple vehicles were involved in two separate collisions between Reynolds Road and Mallorytown Road, shutting down all eastbound lanes in the area. Many minor injuries were reported, and one child was taken to hospital with serious injuries. A total of four people were taken to the hospital. Police estimate about 25 vehicles were directly involved, with many more motorists trapped between the crash sites or stuck in the resulting traffic backup.

Officers report responding to dozens of collisions across the region since early morning as blowing snow and poor visibility continue to create dangerous driving conditions. Police are urging people to avoid unnecessary travel and are warning that many drivers are not adjusting their speed or driving behaviour to match winter conditions.

Motorists caught in the standstill are being asked to remain in their vehicles and follow instructions from emergency crews on scene. Police say the highway closure is expected to last for an extended period.