Two vacant houses were destroyed and a third lived-in home was damaged in an early morning fire in Vancouver's Strathcona neighbourhood — and Vancouver firefighters say the event illustrates one of the problems with abandoned houses.

More than 40 firefighters responded to the 1000 block of Keefer Street, which is between Hastings and Venables streets just west of Clark Drive, at 3:30 a.m. PT Saturday morning.

Vancouver Fire and Rescue Services Acting Battalion Chief John Dennis said the fire, though cause unknown, started in an abandoned house at the end of the street.

"When we arrived it was fully engulfed. That fire managed to spread to the adjoining building and fully engulfed that one as well. And then it tried to impinge on a third," he said. "Crews did a great job of stopping it at that point, with minor damage to the third building."

Amanda Giacomazza - 1000 block Keefer Street fire

Amanda Giacomazza is one of the tenants forced out by the Keefer Street fire early Saturday morning. (CBC)

The tenants living in the third, damaged house escaped unharmed, he said.

Amanda Giacomazza, one of those residents, said they thought at first a car was on fire outside. When she went to get a better look from an upstairs window, the orange-painted room glowed from the light of the flames outside.

"You could just feel the heat everywhere," she said.

She and her housemates grabbed some of the their belongings and got out. From the backyard, they then watched as windows shattered and flames flared up high and spread to the second house.

"I was quite shocked. A little started," she said. "You definitely don't want to wake up to this sort of thing."

1000 block Keefer Street fire, Aug. 2, 2014

The fire began in one abandoned house, spread to a second abandoned house, and caused minor damage to a third house were some tenants were living. They were not harmed. (Siavash Dezvareh/CBC)

Abandoned house hazard

Dennis said investigators would be working through the day to try and determine how the initial blaze began, but the fact that it started in an abandoned house and quickly spread to a second does not entirely surprise him.

1000 block Keefer Street fire

Vancouver Fire and Rescue Services Acting Battalion Chief John Dennis said fire crews try to keep tabs on vacant properties in their areas. (CBC)

"Both the buildings on the end were abandoned, which was one of the problems that we'd been worrying about. We knew that this was an issue," he said.

Dennis said that the fire crews in most districts of the city keep tabs on the abandoned buildings in their areas.

"We know there's always structures in the city that are abandoned and in transition from renovation to demolition," he said. "Any structure that's been abandoned for a long period of time is always a worry to the fire service."

1000 block Keefer Street fire, Aug. 2, 2014

Flames engulfed two vacant homes in the 1000 block of Keefer Street early in the morning on Saturday, Aug. 2, 2014. (Siavash Dezvareh/CBC)