Flames broke out around 1:30 p.m. inside an apartment on the third floor of a six-story building on Union Street in Crown Heights.
Sixty firefighters from 12 FDNY units responded and were able to bring the fire under control quickly.
Firefighters said the flames were mostly contained to that one unit.
The victim has not yet been identified, but police sources tell Eyewitness News that he was a retired NYPD officer.
The Fire Marshall is investigating the cause of the fire.
According to the US Fire Administration, as of February 23, there have been 36 fatal fire deaths in New York state.
Eyewitness News is tracking crime and safety across New York City and in your neighborhood
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