An Air France jet thought to be carrying 252 passengers on board has caught fire after skidding off the runway at Toronto's Pearson airport.
The plane, an Air France A340 jet, crashed into a ravine after running off the end of the runway. Black smoke billowed from the wreckage as the aircraft burned.
"An Air France plane landing on runway 2-4 went off the end of the runway in the area of Convair Drive and the 401 area in Mississauga," Peel police Sgt. Glyn Griffiths said.
Canadian television quoted police as saying that the pilot and a number of passengers been taken to hospital.
Emergency workers have told a local radio station that most of the passengers were safe.
Rescue vehicles rushed to the scene, which was in a wooded area near Highway 401, Canada's busiest highway.
The aircraft was due to land at the airport at 3.15pm (local time). There was no immediate word on casualties.
Witnesses told Canadian television stations that the plane had apparently skidded off the runway after landing in rainy conditions.
It was too early to say what might have caused the plane to miss the end of the runway.
Live TV pictures showed huge clouds of black smoke and orange flames coming from the fuselage of the plane, which was off the end of a runway lying close to a main traffic artery.
Air France's Web site showed that flight 358 left Charles de Gaulle airport in Paris was due to arrive at Pearson's terminal 3 on Tuesday afternoon.
A spokeswoman for Aeroports de Montreal said no flights were landing at Pearson airport in Toronto following the accident.
Leah Walker, a radio reporter in Toronto, said she saw a third of the plane fall and that the rest became a fireball. "This plane attempted to land in some very fierce weather we had today," she said.
Thunderstorms create the possibility of wind shear, the sudden, dangerous air currents that can dash an airplane to the ground as it takes off or lands.
The last major jumbo jet crash in North America was on Nov. 12, 2001, when American Airlines Flight 587 lost part of its tail and plummeted into a New York City neighborhood, killing 265 people. Safety investigators concluded that the crash was caused by the pilot moving the rudder too aggressively.