Three people are confirmed dead after an overnight fire tore through an apartment building in Drummondville, Que.

Police confirmed the fatalities Thursday evening, after investigators spent the day at the 36-unit building on Des Merisiers Avenue, about 100 kilometres northeast of Montreal, trying to account for people.

Drummondville fire

On Thursday afternoon, emergency crews were seen pulling out bodies from the rubble. (CBC)

At first, three people were considered missing. During the afternoon, CBC reporters on site witnessed emergency crews carrying out what appeared to be bodies from the third floor of the building.

By 7:30 p.m. ET, police confirmed the bodies of the three people were pulled from the rubble. A coroner's investigation will determine their identities.

Eight people were injured in the fire and are being treated in hospital. The extent of their injuries is unknown.

Burned 'like a house of cards'

Isabelle Sawyer

Isabelle Sawyer, one of the residents of the Drummondville, Que., building in the deadly fire overnight, says it burned like a 'house of cards.' (Rebecca Ugolini/CBC)

Isabelle Sawyer, a resident of the building, said she managed to get out after her neighbour banged on her door and warned her about the fire.

"It burned like a house of cards," Sawyer said.

"I heard people screaming on the balconies. It was apocalyptic."

Sawyer said many of the units in the building are one-bedroom, occupied by single people, many with no insurance and on social assistance.

Aurélie Guindon, a spokeswoman for the provincial police force, Sûreté du Québec, said the cause of the fire is under investigation.

"We're aware of reports circulating that it may have been caused by a cooking fire, and that's one of our hypotheses," she said.

Quebec Fire drummondville

Much of the apartment building was destroyed in the fire that broke out overnight. (Ryan Remiorz/Canadian Press)

An amateur video posted to Facebook by a local resident showed the speed at which the fire spread through the building.

Chantal Allard, who lives nearby, said the noise of people screaming woke her up. 

At first, Allard said she thought people were partying, or getting into trouble, but then she saw the flames "and the people leaving the building."

Firefighters got the blaze under control at about 3 a.m.

Investigators spent most of the day Thursday checking the building for potential victims, as well as to determine the cause of the fire. Police spokeswoman Geneviève Guilbault said she is not sure how many people live in the building.

By 1:30 p.m., residents were allowed back inside.

Emergency services left the scene Thursday evening.

The Red Cross is assisting with relief efforts.

Police are asking people to call 1-800-659-4264 to let them know if a resident of the apartment building is missing — or is safe.

With files from The Canadian Press