People living inside a multi-family residential home in Bowmanville, Ont., escaped a fire unharmed Tuesday afternoon, according to fire officials.

The blaze began around 1 p.m. at the 100-year-old building on Ontario Street.

Kyle Hill, a resident of one of the apartments, said he was asleep preparing for a night shift when he was awoken with a bang on his door.

"I could smell smoke already. I was in a panic. I didn't even grab my wallet or the keys to my car," Hill told CTV Toronto.

Another tenant said the blaze started in the roof and spread "very quickly."

At the height of the fire, flames were shooting out of the roof and part of the structure collapsed.

Despite the damage, officials said the old building could be salvaged.

"We've had our chief building official here. He said the structure is still sound. He's allowed us back in so we can start salvage and overhaul," Clarington Fire Chief Gord Weir said.

The cause of the fire is under investigation.

With a report from CTV Toronto's Scott Lightfoot