Police admit they 'lost sight' of speeding van minutes before deadly Highway 401 wrong-way crash

Officers pursuing a robbery suspect driving a cargo van — later involved in a deadly wrong-way crash east of Toronto — initially "lost sight" of the vehicle minutes before it barrelled onto Highway 401, according to a new police account of the cascade of events.

The report, submitted last month to the Durham Regional Police Service Board, lays out the most detailed public timeline offered so far by the agency involved in the chase.

The high-speed pursuit the evening of April 29 ended in a fiery pileup in Whitby, Ont., that killed four people, including three-month-old Aditya Vivaan and his two grandparents. The incident remains the focus of a probe by the Special Investigation Unit (SIU), Ontario's civilian police oversight agency.

In the recent report, Durham police confirmed "communications received a call from an off-duty officer regarding a commercial robbery from the LCBO in Clarington." A dispatcher gave Ontario Provincial Police a similar account of what set off the chaotic sequence of events in audio later posted online.

"The suspect had pulled a knife on the off-duty officer who had intervened to prevent the [liquor store] theft," Durham Regional Police Insp. Doris Carriere wrote in the report.

It's the first time the police agency publicly acknowledges an interaction occurred between the suspect and an off-duty officer at the LCBO.

When the man, later identified as Gagandeep Singh, 21, took off in a U-Haul van, the officer "strategically followed the suspect vehicle and disengaged when officers in marked cruisers caught up to the suspect vehicle," according to the new report.

After the Durham police cruisers caught up with the U-Haul, officers said they "lost sight of the vehicle." The report does not disclose where or how the van driver managed to evade the pursuing officers, but says "a brief time later, [the vehicle] was again located in Oshawa."

Oshawa is located about nine kilometres west of the Bowmanville liquor store where the chase began, within the regional municipality of Clarington. Roughly 20 minutes elapsed between the alleged robbery and the deadly crash, the SIU previously said.

According to police, the U-Haul "struck a cruiser" before entering the busy eastbound Highway 401 in the opposite direction of traffic. 

In amateur videos reviewed by CBC News, 20 police vehicles could be seen pursuing the cargo van on either side of the highway. At least seven gave chase in the opposite direction to traffic.

Durham police have not said publicly why so many vehicles joined in the pursuit.

"In my mind, those events are not separated," Durham Regional Police Chief Peter Moreira previously said, referring to the robbery, followed by the chase and crash. "I'm going to let the SIU complete their investigation."

The police watchdog's probe is focused on two unnamed officers. "Neither subject official has agreed to an interview or [to] provide notes, as is their legal right," SIU spokesperson Kristy Denette told CBC in late June.