The DeKalb Fire Department is investigating a fire at a local apartment early Monday morning that caused $100,000 in damage.

Firefighters responded to the fire at 1212 Varsity Blvd. at 1:16 a.m., with reports of occupants trapped inside. That report later proved to be unfounded.

Firefighters faced heat and smoke in the building on arrival but brought the fire under control in 45 minutes, DeKalb Fire Lt. Karl Froehlich said in a press release.

Fifty-two firefighters from DeKalb and seven other departments were called to the scene.

The cause of the incident is under investigation, DeKalb Fire Chief Lanny Russell said.

The fire was contained to Apartment 3, where it originated, but the bulk of the damage was caused by smoke throughout the building, he said.

“It was just running down the walls,” Russell said.

One firefighter and one civilian were treated and released for a minor back injury and smoke inhalation, respectively.

Although several of the building’s occupants were displaced, Russell said he expected them to return soon after maintenance workers and code enforcement officials make sure the building is hospitable.

The Red Cross assisted residents with temporary housing.