There were 133 passengers and five crew members aboard flight AC624, which left Toronto just before 9 p.m. Saturday for a scheduled midnight landing at Halifax Stanfield International Airport, the airline said in a statement.
Air Canada said on Twitter shortly before 8 a.m. that 18 people who were taken to the hospital had been released. There was conflicting information on the number of people injured shortly after the accident but Air Canada and the airport later said they verified 23 were transported by Emergency Health Services to area hospitals.
None of the injuries were considered life threatening, Air Canada said.
The Halifax area was under a snowfall warning at the time, with as much as 20 centimetres of snow forecast for the area. There was no indication from officials on whether the weather played a factor in the landing.
Air Canada would not provide a spokesman to respond to questions. It tweeted that the plane had "exited" the runway.
Passengers on board the plane said they believe the aircraft hit a power line as it came in to land but there was no official confirmation of it making contact with anything before the accident.
Airport spokesman Peter Spurway said the aircraft touched down at about 12:35 a.m. and he didn't know if runway conditions played a role in the landing.
"It came down pretty hard and then skidded off the runway," said Spurway, who added that two people who were taken to the hospital required "urgent care" but he couldn't comment on the extent of their injuries. All the other people were treated for bumps and bruises, he said.
The power went off at the airport, which meant an emergency response centre had to be moved to a nearby hotel, Spurway said. Nova Scotia Power said in a tweet that power was restored to the airport, but it didn't indicate why the electricity went out.
Randy Hall and his wife Lianne Clark were on their way home from a Mexican vacation when they said the plane ran in to trouble as it landed.
"We just thought that we were landing hard. And when the ... air bags started to deploy and you saw things falling on the floor, we said, 'Oh no. We've got to get out,' " said Clark, a computer consultant
"We just opened the doors when we landed and everyone started to pile out."
Hall said he believes the jet hit a power line before it landed hard on the runway. There were sparks but no fire, he said.
"We were just coming in to land and there was a big flash," said Hall. "The plane came down, bang! It jumped up in the air again."
The aircraft skidded for a long time before coming to a stop, said Hall, who is retired and lives in Mount Uniake, N.S.
"We were sliding along on our belly," he said.
Hall said the aircraft hit so hard, the landing gear and at least one of the engines was ripped from the plane.
"I was looking out and I saw the landing gear go and I saw an engine go," said Hall.
"We have no information to provide on the condition of the aircraft at this point," wrote a spokeswoman.
Spurway also wouldn't comment on the condition of the plane.
It cannot be determined in photographs released by the Transportation Safety Board of Canada whether the engines are still attached to the plane. A photo of the front of the plane released on the board's Twitter account shows what appears to be the engine on the starboard side of the plane crumpled under the wing, while the view of the port side wing is obscured by an emergency slide.
Cpl. Greg Church of the RCMP said a power line south of the runway outside airport property was damaged, but Nova Scotia Power couldn't be reached to comment on what caused the damage.
Hall said passengers left the plane immediately but they were left standing on the tarmac, some in their stocking feet, for more than an hour as they were lashed by wind-whipped snow before buses arrived.
The couple, who were wrapped in blankets as they spoke, said they saw some people with bloody faces, but it didn't appear that anyone was seriously injured.
Spurway said emergency responders were at the scene within 90 seconds and their first priority was dealing with any possibility of fire.
Fire trucks had limited space and the power outage complicated getting buses to the scene, said Spurway.
"Once it was determined that threat was out of the way, they put some of the passengers in fire trucks to get them out of the weather on a triage basis," he said.
"There was a large tarp used to protect some of the passengers but they were out there for a while, that's for sure, until the buses arrived."
Spurway said there will be a review of the airport's response.
Spurway said the plane was flying in a southerly direction when it landed on the airport's main runway, adding that it is up to pilots to decide whether it is safe to land in bad weather based on information relayed from ground crews to the tower.
Dominic Stettler, 31, of Wolfville, N.S., said people on board the plane responded with level heads.
"I think we hit a power cable, there was a lot of sparks," he said. "We hit the ground, we came up and then we slid on the runway for quite a long time. We just kicked the doors out and jumped onto the wing and then ran because we just wanted to get away from the airplane in case of explosions or anything."
Stettler said people were helping each other after they got off the plane.
"A woman offered me her jacket because I was shivering and pulled me into a tight warm hug and we just sat there for a while. It was kind of special actually," he said.
The flight crew told the passengers that conditions at the airport weren't good and they would circle for an hour to see if things improved, he said. If they didn't, Stettler said the flight was going to head to Moncton, N.B.
"And then there was a window of visibility and we went for it," said Stettler, 31, the father of two boys and a girl.
The landing didn't feel right when the plane touched down, he said.
"I actually didn't know we (were) on the runway. I thought we might be on a field and that at any point we could run into a tree or some obstacle. While we were sliding, I just thought about my boys and my family," he said.
Once he was off the plane, he ran to get safely away from the aircraft.
"I tripped over a big metal object, which must have been one of the components," Stettler recalled. "It was just completely surreal. Parts of the plane were scattered across. I don't really want to say too much because I don't want to terrify people. But yeah, it was surreal. It was very surreal."
Also on HuffPost