Twelve people were forced from their homes on Boxing Day after a fire broke out in a small apartment complex in Surrey.

The blaze happened at about 7:30 a.m. PT in the 8300 block of Scott Road, and sent black smoke billowing into the sky.

The flames forced residents to leave their apartments quickly, some without their shoes.

"I was the first one out of the apartment and banging on everyone else's doors," said Luke Trojek. "Then I ran back and made sure that everyone got out."

Roger Donelle, who lives behind the building, called 911 and ran towards the fire to wake up one of the residents.

"He was surprised. I said 'Fire, get out!'... and oh, man, he got out of there quickly."

Four people were trapped on a ledge outside the building and were rescued by Delta firefighters using a ladder.

Strange sounds before fire began

A number of residents say they heard strange sounds inside the building just before the fire started.

Fire in Surrey apartment building

The fire was at the rear of the building at 8362 Scott Road. The cause of the blaze is still unknown. (CBC)

Surrey Fire Department battalion chief Brian Carmichael said the cause of the fire is still not known, but the damage is extensive and the structure will have to be rebuilt.

"I'm not saying it's suspicious. I'm saying it is under investigation," he said. "There are all sorts of things that happen under fire conditions like popping and window smashing."

Ken Clarke, who works at Scottsdale Bowling across the street, said at least 10 or 12 fire trucks from Delta and Surrey were on the scene.

"Several residents were out wandering round the streets just wrapped in blankets," Clarke told CBC News.

Residents unlikely to return home soon

It's unlikely the residents, many of whom are low-income, will be able to return home any time soon.

Emergency services have put them up in motels for three nights and the building's landlord is also trying to help them out.

"He understands some of these people don't have much," said realtor Shahim Soheili, who spoke for landlord Benjamin Kutan.

"And that's one of the reasons he payed each suite $100 out of his own pocket so at least they have some cash for the next couple of days."