The aircraft, an Airbus A320, touched down about 1,100 feet short of the runway, said Mike Cunningham, a regional manager of air investigations at the Transportation Safety Board of Canada. From there, it hit an antenna array that's part of the airport's landing system and severed a power line.
That caused "significant damage" to the plane and cut off power to Halifax Stanfield International Airport
in Nova Scotia, he said.
The plane skidded for another 1,100 feet on its belly before coming to a stop.
Investigators haven't determined yet what caused the accident, Cunningham said.
The plane's so-called black boxes are on their way to engineers for analysis, he said, and dozens more investigators are set to arrive at the crash site Monday.
"Obviously it's too early to draw any conclusions. ... These things are always very complex. It takes quite a bit of time to get to the underlying factors."
Twenty-five people, including the two pilots, were treated for minor injuries at a hospital, said Klaus Goersch, Air Canada executive vice president and COO.
By Sunday afternoon, all but one passenger was released.
Goersch called the incident "very unsettling" and said that the company is cooperating with authorities in an investigation.
Questioned by reporters, Goersch said that the weather was safe enough for a plane to land.
He declined to speculate on a cause for the crash, saying investigators will make that determination.
Video distributed by CNN partner CTV Network
appeared to show the plane stationary, with part of the nose missing and a nick in one wing. The video also showed a downed power line and damage to a small airfield tower.
Air Canada Flight 624 left Toronto late Saturday for Halifax. Air Canada said the passenger list indicates the plane had 133 passengers and five crew members on board.
Heavy snow was reported at the time of the landing, but Peter Spurway, an airport spokesman, said it was unclear if it had played a role in the accident.
Scott Murray told CNN partner CBC News
that he was waiting at the airport for his father, who was on the flight. He said his father had called to say that "the plane crashed and he's all right."
Air Canada said it would cooperate fully with authorities' investigation into what happened.
The airport also lost its electricity supply for part of the night.
"Power is out at HFX airport," tweeted CBC reporter Chris Ensing. "Pitch black with exit lights on. Blowing snow."
Nova Scotia Power tweeted later that it had restored power to the airport.