HOUSTON -- Dozens of families lost their homes and belongings in a three-alarm fire that damaged three buildings at a northwest Houston apartment complex, KPRC Local 2 reported.

Houston firefighters said the fire on Monday was the second blaze in a month at the Timbers of Inwood Forest Apartment Homes on West Gulf Bank Road near Green Lawn Drive.

The fire broke out at about 8:45 p.m. and swept through two occupied buildings and an empty building, officials said.

"It just kept going. It got up into the attic," District Chief Tommy Dowdy said. "Once it got up into the attic I'm sure it traveled. Once it gets to that point, there's no stopping it."

Residents ran for their lives after two residents alerted them to the blaze.

"Nobody was out and nobody knew," resident Cherrell Woods said. "We went through all the apartments knocking on doors and windows trying to get everybody out. Some people we didn't know if they were home or what, so we just went through and knocked on all doors."

Everyone made it out safely, but most of them do not have a home to go back to.

"I don't know anything, so I'm standing here waiting patiently," resident Lisa Thomas. "I want to see what can I salvage, if I can salvage anything."

Officials said a total of 32 units burned. At least one of the buildings will be demolished because it is not safe.

One firefighter was transported to a nearby hospital for treatment for heat exhaustion.

Arson investigators plan to search for a cause of the fire on Tuesday. They were not able to enter the building overnight because hotspots flared up.

Apartment managers relocated the residents to other units at the complex. The Red Cross is helping the displaced families.