A 65-year-old woman from Calgary is dead after a three-vehicle crash near Burlington that snarled traffic and sent three people to hospital Monday, police say.

On Tuesday, Ontario Provincial Police identified Rassina Al-Yafi from Calgary as the woman who was killed in a collision on the QEW in the Toronto bound lanes east of Appleby near Burlington.

According to police, a GMC Sierra rolled over because of a collision around 4:38 p.m. Monday. Al-Yafi was thrown from the truck, killing her.

OPP Sgt. Kerry Schmidt told CBC Hamilton that investigators are still working to piece together how the crash happened. “There are conflicting stories,” he said. Originally, police thought the accident was a “simple chain reaction” situation where the cars piled into one another, but Schmidt said it “may be a little more complicated than that.”

There were four other people in the car at the time of the crash, police say.

The driver, a 33-year-old man from Mississauga, sustained minor injuries, while a 32-year-old woman from Mississauga and a 70-year-old man from Mississauga sustained serious injuries. A 13-month-old baby was in the car, but wasn’t hurt in the crash, police say.

The drivers of the two other vehicles – a 29-year-old man from Mississauga driving a Honda and a 28-year-old-man from Niagara on the Lake Driving a Ford – weren’t hurt.

Police aren’t yet sure if speed or alcohol were factors in the crash, Schmidt says.

Officers from the Burlington detachment of the OPP and the police traffic support unit are still investigating. Anyone who saw what happened or with information on the crash is asked to call police at 905-681-2511.

This was the second crash in a matter of hours on the QEW near Burlington Monday. A 60-year-old man was airlifted to a Hamilton hospital after a garbage truck rolled over on the eastbound lanes of the QEW at Guelph Line around 12:10 p.m.