Highway 400 between Finch Avenue West and Highway 7 was closed in both directions after a truck loaded with liquid oxygen overturned Monday afternoon, creating an explosion risk.

A tractor-trailer loaded crashed with a minivan and overturned sometime around 1 p.m. The truck came to rest on its side, prompting emergency responders to rush to the scene, including police, firefighters and a hazardous materials team.

No injuries were reported.  Police believe the slippery conditions caused by an overnight ice storm may have contributed to the accident.

Police evacuated the area 300 - 500 metres around the scene by diverting traffic away and closing the highway. All ramps leading to and from the highway were also closed.

Ontario Provincial Police Sgt. Cam Woolley said the location of the crash is safely away from residential and commercial areas.

"We got pretty lucky," Woolley said.

"If this was going to happen anywhere, this is probably the ideal spot. This is near the intersection of two major highways, so there are no residences nearby and very few businesses.

Southbound traffic was diverted to Highway 407 or Highway 7. Northbound traffic was sent to Finch Avenue, which is reportedly causing traffic tie-ups and delays.

"It's really been a terrible day for rush hour traffic," Woolley said.

He added that the only safe way to remove the truck is to transfer the load to another tanker.

"But it will probably take at least three to four hours to transfer the load ... So there's no chance of the 400 opening for this afternoon's rush hour."

Woolley anticipated that it would take until 2 a.m. Tuesday morning to complete the transfer of liquid oxygen from the overturned tanker and remove it from the highway.

The accident occurred when the minivan and truck collided, causing the truck to lose control and overturn.

Woolley noted that some of the liquid oxygen was being vented from the tanker truck and that fire crews were on stand-by at the scene.

Traffic snarled around the busy highway which connects Toronto with communities north of the city. Slippery road conditions further complicated the situation.

Police reported about 600 collisions on highways patrolled by the OPP. That figure did not include accidents in areas served by other police forces.