The third-alarm fire broke out inside one home on Marshall Street in Elizabeth just after 1 a.m. and quickly spread to two more.
Firefighters arrived to find heavy fire on the first floor extending to the second floor.
There was a report of a person inside, but firefighters were unable to reach him.
The victim, Cesar Prats, was killed when flames ripped through his first-floor apartment.
The victim's grandson was in Queens when he got the call that his grandfather had died.
He arrived at the scene and described his reaction.
"Sadness, anger, resentment. I had seen him days ago and was meaning to come over tomorrow after work and now I can't", he said.
The cause of the fire is under investigation.
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