The blaze broke out at around 7 p.m. Monday, Oct. 7, in Seaford.
First responders observed the second floor of the home on Crescent Cove Drive engulfed in flames.
The Seaford Fire Department extinguished the flames, but the residence sustained extensive damage.
An 85-year-old man was removed from the residence and transported to a nearby hospital, where he was pronounced dead just after midnight on Tuesday, Oct. 8, by a hospital physician. The man's identity has not yet been released. No other injuries were reported.
The Nassau County Fire Marshal and Arson/Bomb Squad Detectives also responded to the scene.
The investigation is ongoing.
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