Why did the plane crash in Toronto and how did everyone escape?

Investigators are trying to establish exactly what happened when eighty people miraculously escaped after a Delta Air Lines jet dramatically flipped upside down as it landed in Toronto.

It's not clear what went so disastrously wrong as the plane - which was carrying 76 passengers and four crew - touched down on Monday.

Eighteen people were injured, but the fact nobody was killed has been hailed as remarkable.

Where was the flight coming from?

The twin-engine Mitsubishi CRJ-900LR jet was coming to the end of a flight from Minneapolis in the US (around 700 miles away) when the landing at Toronto's Pearson Airport went catastrophically wrong.

Weather conditions in the Canadian city, which has been blanketed by snow recently, saw winds gusting to 40mph when the flight attempted to land at around 2.15pm local time (7.15pm UK time) on Monday.

Communications between the tower and pilot were normal on approach.

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What happened when it tried to land?

For reasons that have yet to be established, the 118ft jet flipped over onto its back after touching down on the tarmac - leaving passengers hanging upside down in the cabin.

Peter Carlson, a passenger travelling to Toronto for a paramedics' conference, said the landing was "very forceful".

"All the sudden everything just kind of went sideways and then next thing I know it's kind of a blink and I'm upside down still strapped in," he told CBC News.

Emergency responders reached the plane within a few minutes, Toronto Pearson Fire Chief Todd Aitken said, and the operation "went as planned".

Pictures and videos from the scene show the plane's fuselage seemingly intact as firefighters doused what was left of the fire, with what appear to be scorch marks visible near the tail section.

Passengers were able to climb out and walk across the tarmac.

Was anyone injured in the crash?

All 80 people on board the aircraft survived and Mr Aitken said 18 passengers were taken to the hospital.

Earlier in the day, Ornge air ambulance said it was transporting one paediatric patient to Toronto's SickKids hospital and two injured adults to other hospitals in the city.

A spokesperson for the Peel Region paramedic service told Sky News the injuries ranged from minor to serious - but none were life-threatening.

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'Crew did a remarkable job'

Former air traffic controller Todd Yeary said it was "remarkable" nobody was killed in the crash.

Asked about the weather, he told Sky News: "There's some question about whether or not there were extreme wind gusts at about the time the flight was touching down, and whether or not that had any impact on the ability to control the landing."

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He said ice on the runway could have been a factor as well.

"What we do know is the crew did a remarkable job to make sure that everybody got off that airplane safely," he added.

Mr Aitken, the fire chief, has said "the runway was dry and there was no cross-wind conditions".