An unattended stove sparked the April 2 fire inside of a Westgate Arms apartment building that left one man hospitalized and roughly 30 people without a home, fire officials said.

The three-alarm blaze began inside Apt. 12 of the three-story building at 25 Oak Ridge Avenue just before 6 p.m. Firefighters arrived on the scene within three minutes of the first report, though officials said the fire later extended into the walls and the ceiling, forcing crews to use thermal cameras to track down the remnants of the blaze.

Apartments on the second and third floor closest to Apt. 12, which was left gutted by the blaze, suffered some damage from the fire, according to apartment management.

Repairs are expected to take up to three weeks or more to complete, and in the meantime, residents of the 25-unit apartment building have been either given rooms at the Red Roof Inn or asked to stay with friends or family.

Though she was not home at the time, resident Erin Torrey said she had “a panic attack” when her boyfriend called to let her know about the fire. Standing outside the building on Friday with a week’s worth of work clothes, Torrey said she and her boyfriend were staying in Hampstead for the time being.

Her first-floor apartment had been left undamaged by the fire, but she expected it would be more than a week before she could return to the home she’s lived in for a year and a half.

“We were really lucky on the ground floor,” she said. “It barely even smells anymore.” The American Red Cross was also on hand on Friday to give assistance to residents who have been forced to relocated for the time being because of the fire.

Though one unidentified man was transported to Elliot Hospital in Manchester for smoke inhalation, officials said he was released on Friday.

Salem received mutual aid from Windham, Derry, Hampstead, Pelham and Methuen and Haverhill, Mass., while firefighters from Atkinson and Plaistow provided coverage for the rest of the town during the fire.