D.C. firefighters rescued an unconscious woman from a burning Northwest apartment Thursday night, fire department officials said.

Firefighters who arrived in the 800 block of R Street raced inside the ground-floor unit, where they found the woman about 8:30 p.m., said Vito Maggiolo, a fire department spokesman. Rescuers carried her outside and she was taken to a hospital in critical condition.

The garden-style apartment sustained heavy damage, but firefighters prevented the fire from damaging other units in the three-story building. However, several residents were displaced, Maggiolo said. Officials asked the Red Cross to assist those residents.

The cause of the fire was under investigation.