The fire, which is now under control took place on Flushing Ave.
The firefighter who died has been identified as 47-year-old Lt. Richard Nappi.
Mayor Bloomberg said during a news conference Monday evening, "While battling the blaze, Lieutenant Nappi overheated, suffered exhaustion and collapsed. He was rushed here to Woodhull, but despite the best efforts of medical personnel, he tragically died."
Before joining the FDNY 17 years ago, he served as a state parole officer and a caseworker for Suffolk County, on Long Island.
He leaves behind a wife and two children.
"He has a wife Mary Anne, and a 12-year-old daughter and an11-year-old son. I just spent some time with Mary Anne who is here to express the condolences of all the people of New York and thanked them for the ultimate sacrifice that their family made to keep New Yorkers safe," Bloomberg said.
The mayor says Nappi also responded to the World Trade Center on 9/11.
"On the morning of September 11th, '01, the FDNY's, and New York City's, most tragic day, Lieutenant Nappi was assigned to Engine 7 on Duane Street in Lower Manhattan, where he responded with valor to the World Trade Center attacks. In the days that followed, he helped save and rebuild our city in ways that all New Yorkers, in fact, people all over the world, understand," Bloomberg said.
In addition to his work as a member of FDNY, Lieut. Nappi also served as a volunteer firefighter and Deputy Chief Instructor with the Suffolk County Fire Academy in Yaphank.
Lieutenant Richard Nappi loved being a firefighter so much he trained young aspiring firefighters how to become New York's Finest.
Even after pulling a long shift for the FDNY many times.
"He used to come here on his way from the city. I'd find him and say, 'Rich you're not on the schedule.' He'd say, 'Somebody's bound to call in. I'm available.' That was his favorite saying, 'I'm available,'" Chief Bob Hopkins said.
Chief Bob Hopkins says the 47 year old worked as a field instructor for five years at Suffolk Fire Academy in Yaphank.
The 17-year-veteran joined the FDNY in '94, working in Lower Manhattan, Queens, and Brooklyn.
Flags are at half staff outside the Farmingville Fire Station near Lieutenant Nappi's home.
Fellow firefighters and long time friends say their thoughts and prayers are with his family.
"We're going to miss him. Terribly. It's hard to replace somebody like that that's so happy with their life," Chief Hopkins said.
Five of the injured firefighters were taken to the Woodhull Hospital. One is listed in serious condition. Another firefighter was transported to Kings County Hospital.
It is unknown what caused the fire.
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