Four people, including a baby, have died in a collision on Highway 401 in Whitby, Ontario, late Monday after a police pursuit of a driver allegedly involved in a robbery, according to the Ontario Police Watchdog.

The Special Investigations Unit is expected to provide more information at a press conference near the scene of the accident today, Tuesday.

Ontario Provincial Police say the eastbound lanes of the busy highway remain closed between Lake Ridge Road and Brock Street, and the entire highway was closed overnight, but the westbound lanes reopened to traffic shortly before 7 a.m.

According to Durham Regional Police, the fatal incident occurred after a suspect in a theft entered the eastbound lanes driving in the
wrong direction.

Sergeant Joanne Bortolus said officers initially responded to a robbery call in Clarington, east of the collision site, around 7:50 p.m.

Bortolus explained that the suspect fled in a vehicle and police chased him.

The Special Investigations Unit is investigating the conduct of police officers in incidents that may result in death or serious injury, or the discharge of a firearm.