CHICAGO — Three people are hospitalized after a fire broke out at a senior apartment building on the city’s Northwest Side.

Emergency crews responded to the West Byron Place Senior Apartments, located at 2815 West Byron Street, around 6:40 a.m. Tuesday. Officials said a fire was located in an apartment on the fourth-floor and was quickly extinguished.

According to officials, one person was removed from the unit in grave condition.

The Chicago Fire Department said firefighters performed CPR on scene before moving the victim to the street-level where medics continued working to save her life. She was then rushed to an area hospital.

The fire department said they canvassed the building to make sure no other residents needed help after the fire.

Officials said there were working fire detectors in the building.

The cause of the fire remains under investigation.