David F. Warde Jr. was pronounced dead at the scene of the 6:30 a.m. first-floor apartment blaze on Forest Avenue, Bergen County Prosecutor Gurbir S. Grewal said.
"Family members living on the second floor were able to flee the burning structure," Grewal said.
They had their pet rabbit with them.
Paramus police "found a heavy smoke and fire condition" in Warde's apartment and then his body soon after, the prosecutor said.
Firefighters needed 45 minutes to knock down the blaze, which blew through the roof of the nearly 65-year-old house at Forest and Brookfield avenues, Fire Chief John Niland said.
Flames broke out on the first floor and quickly spread, gutting one of the apartments and damaging the other.
Oradell, River Edge, Rochelle Park and Saddle Brook firefighters provided mutual aid.
Daily Voice New Jersey Managing Editor Cecilia Levine contributed to this story.
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