Airport CEO Deborah Flint said investigators will be reviewing the aircraft on the runway for the next 48 hours, adding that this was “not the time” to speculate on the cause of the crash.

The Delta Air Lines flight from Minneapolis skidded along the runway with flames visible before it came to a halt upside down.

Twenty-one people were injured, of which 19 have been released from the hospital, authorities said on Tuesday. The two patients do not face life-threatening injuries.

There were 76 passengers and four crew on board the 16-year-old CRJ900 aircraft, made by Canada’s Bombardier company.

Injuries at the time of the crash ranged from head injuries to back sprains, and nausea and vomiting due to jet fuel exposure, a representative for Peel Regional Paramedic Services said.

Experts told the BBC it was miraculous that everyone survived the crash, adding that the swift response of flight attendants and emergency crews helped save people, as well as plane safety improvements.

Passengers on board said they were hanging upside down in their seats and had to release themselves, falling on to the ceiling before clambering out on to the snow-covered tarmac. Firefighters quickly came to the rescue.

“We were upside down hanging like bats,” passenger Peter Koukov told CNN.

A child was among the injured but was in good condition as of Tuesday morning, the Hospital for Sick Children in Toronto told the BBC’s US partner CBS News.

Although the airport had been experiencing “extreme” weather conditions, Monday was categorised as a “clear day” for operational recovery following prior disruption, officials said.

Two runways remained closed on Tuesday as the Transportation Safety Board of Canada continued its investigation into the crash.

Toronto was hit by a major snow storm over the weekend, but authorities said the runway was dry at the time of landing and that there were no cross-wind conditions.

Cross-wind conditions refer to when wind blows opposite to the direction of travel which could affect vehicles and aircraft by pushing them sideways and requiring corrective action to maintain control.

Before the crash, authorities said snow had stopped and “frigid temperatures and high winds [were] moving in”.

Audio recording from Pearson’s air traffic control tower, reported on by the Canadian Press, shows the flight was cleared to land shortly after 14:00 on Monday, and that the tower had warned the pilots of a possible air flow “bump” in the glide path from a plane in front of it.

Analysts say it is possible the plane may have struck an item on the runway such as a light when it landed.

The crash is at least the fourth major aviation incident in North America in the past month, including an American Airlines plane in Washington, DC, that collided with a US Army helicopter, killing all 67 people on board.

Images shared on social media show a plane which appears to have flipped over and is lying on its roof on the snow-covered tarmac. It appears to be missing at least one of its wings.

Toronto Pearson airport said it involved a Delta Air Lines flight arriving from Minneapolis, and that “all passengers and crew are accounted for”.

Fifteen people have been transported to hospital in total, the local paramedic service said.

Ontario air ambulance service Ornge said it haddispatched three air ambulance helicopters and two land ambulances to the scene.

The US Federal Aviation Authority (FAA) said the plane involved was Delta Air Lines Flight 4819, being operated by Endeavor Air.

All 80 people on board were evacuated, it said, adding that the Transportation Safety Board of Canada will be in charge of investigating what happened.

Delta said it was aware of reports of the incident, and it was “working to confirm any details and will share the most current information… as soon as it becomes available”.

Video footage shared on social media shows people clambering out of the overturned aircraft, with fire crews spraying it with foam.

Constable Sarah Patten of the Peel Regional Police in Ontario said “there is a plane crash, however we don’t know the circumstances surrounding it at this point,” according to the news agency Reuters.

“It is my understanding that most of the passengers are out and unharmed but we’re still trying to make sure so we’re still on scene investigating,” she said.

Ontario Premier Doug Ford said provincial officials are in contact with the airport and local authorities and will provide any help that’s needed.

After the crash, the airport’s arrival and departure boards showed scores of delays and cancellations to flights.

The FAA said there was a ground stop at the airport – which requires aircraft to remain on the ground.

Toronto Pearson airport had been experiencing weather-related delays over the last few days, with heavy snowfall and freezing temperatures battering parts of Ontario.