Emergency crews attend a fire after an accident on highway 407, as shown in this still image taken from a video provided by Ontario Provincial Police Sgt. Kerry Schmidt, in Toronto on Wednesday Oct. 31, 2018. Officials say two people have been killed in a multi-vehicle crash that sparked a tanker fire on a major toll highway in the Toronto area. THE CANADIAN PRESS/HO-Ontario Provincial Police-Sergeant Kerry Schmidt **MANDATORY CREDIT**

TORONTO - Two people were killed in a multi-vehicle crash that sparked a massive tanker fire on a major toll highway in the Toronto area on Wednesday, emergency officials said.

The crash happened just before 5 p.m. on Highway 407 in Vaughan, Ont., where provincial police said a westbound tanker crossed several lanes of traffic, jumped a highway median and collided with an eastbound passenger vehicle. Both vehicles burst into flames and were still smouldering hours later.

In a video posted on Twitter, provincial police spokesman Sgt. Kerry Schmidt described the collision as "massive" and said the investigation would take some time.

"I could see smoke from kilometres away as I was heading to the scene," Schmidt said later during a media availability at the scene of the crash.

He said both vehicles were "completely consumed in flames."

Deputy Chief Andrew Zvanitajs with the Vaughan Fire and Rescue Service said the crash involved a passenger car and a tanker trailer carrying liquid fuel.

"When our firefighters arrived, they weren't able to get close to it because of the heat coming off of it," Zvanitajs said in a phone interview.

"But that type of heavy black smoke, and that amount of flame, would lead them to believe that it's a liquid fuel product of some sort ... gasoline or diesel would be the most commonly transported."

Zvanitajs said crews used specialized foam to fight the blaze and the flames were under control by 7 p.m. He expected firefighters would be on the scene for several more hours.

York Region spokeswoman Kylie Doerner said two people were pronounced dead at the scene and no one was taken to hospital. Schmidt later confirmed that both the driver of the passenger car and the driver of the tanker were killed.

Robert Kostiuk was returning home to Mississauga from work in Pickering, Ont., when he saw a vehicle ahead of him go perpendicular and head toward the median.

"When I saw it driving sideways I knew that something was wrong," said Kostiuk, adding that when he saw the tanker burst into flame, he knew it was something big.

Kostiuk, who works for Ontario Power Generation, recorded the accident on his dashboard camera and posted the video to YouTube. He said he's never seen anything this bad.

The highway was closed in both directions between Keele and Dufferin streets well into the evening. Police said delays could continue until Thursday morning.

"Traffic on the 407 and surrounding area is backed up considerably," Vaughan Fire said in a statement Wednesday night.

"Motorists caught in the delay are asked to remain in their vehicles and all others are being asked to avoid the area."

Schmidt said there was some concern about fuel from the tanker spilling into a nearby waterway, and workers from the provincial Environment Ministry were assessing the scene.

He said the extreme heat from the blast has the potential to damage not only vehicles, but the road surface itself, which may need to be repaved.

News from © The Canadian Press, 2018