Police say a 77-year-old woman is dead and seven people were injured in a massive fire in Longwood that caused a partial building collapse Tuesday. 

The fire was reported on Fox Street and Intervale Avenue, according to officials. 

During a news conference Tuesday, Mayor Eric Adams says “quick thinking and action by officers and residents saved lives."

FDNY Chief of Department John Hodgens, says two sisters were found outside of the home that exploded. One of those sisters died from her injuries and the other is in serious condition at the hospital. 

One other person was rescued from the scene by NYPD officers and is in serious condition at this time. Police say two other victims, one 68-year-old woman and an 82-year-old woman, are expected to be OK. 

Council Member Rafael Salamanca in a tweet said the fire was "due to a gas explosion." 

After being off almost all day, the gas has been turned back on for all residents on the block where the fire happened. 

Department of Buildings inspectors was called to the scene. People nearby have been advised to close their windows due to the amount of smoke.

The American Red Cross was also on the scene telling News 12, "Red Cross is on scene assisting affected residents. We will ensure emergency assistance to all who need it. I’ll send more info shortly."

The cause of the fire is under investigation at this time.