The blaze broke out just before 6 a.m. Friday at a four-story building in the 200 block of Buffalo Avenue.
The fire appeared to start in a deli, Deli Grill Fresh Supermarket, on the first floor, sources said. FDNY said the fire was accidental, sparked by a bad power cord behind a refrigerator.
Flames and heavy smoke quickly spread to apartments on the second floor.
Four people were rushed to area hospitals with injuries described as critical. One of those victims, a 79-year-old woman, was pronounced dead at Kings County Hospital.
Another woman and a 50-year-old man were first taken to Kings County Hospital in critical condition and were transferred to Jacobi Medical Center for treatment in hyperbaric chambers.
A 54-year-old woman was taken to Brookdale University Hospital in critical condition
Fire officials said several other people, including two civilians and three firefighters, suffered minor injuries.
Resident Philip Taylor said his family lost everything, and they had to feel their way out of the building's fourth floor.
"By the time we got to the 3rd floor, we couldn't breathe, we couldn't see nothing. So we were basically rushing to get out there, as a blind person would," he said.
Taylor said he had moved into the apartment with his daughter after he became homeless.
"I'm a dual cancer patient. I'm a retired German bricklayer with a post-graduate education. Worked all my life, and I can't ... I can't find... an apartment," he said.
There was no immediate word what sparked the fire.
FDNY fire marshals confirm there was no working smoke alarm found at the scene.
"This was a heavy fire. There was thick, dense smoke everywhere which allowed zero vision. It was a very hot one. I believe the operation at this job was a good reflection of the standards we have in the FDNY. We operated as a unit under intense conditions, good training and diligence. This was a good example of cooperation and units working together as a team to make this rescue," said FDNY Captain Patrick McEvoy in a statement.
The fire department activity led to street closures in the area.
Eastern Parkway service roads were closed from Utica Avenue to Ralph Avenue. Buffalo Avenue was shut down between Eastern Parkway and Lincoln Place.
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