Taftville — Firefighters on Friday evening knocked down a first-floor blaze that sent heavy smoke throughout a three-story apartment building, potentially displacing six residents but injuring no one.

Firefighters responded to 54 Hunters Ave. shortly after 7:20 p.m. and contained the fire to the bottom floor, putting it out within about 30 minutes, Taftville fire Assistant Chief Bill Hadam said in an interview. The road remained closed as of 8:20 p.m.

Hadam said the fire started in the rear of the building but the cause remained unknown. The fire marshal and building inspector were on scene as of 8 p.m., with Hadam noting that a half-dozen uninjured occupants could be temporarily displaced, depending on the severity of fire and smoke damage. All damage was interior.

Firefighters from Taftville, Occum and Yantic departments responded, along with Norwich police, Norwich Public Utilities and the American Red Cross.