Flames broke out just before 3 p.m. Friday on the second floor of the six-story building on W. 145th St. between Amsterdam Ave. and Broadway.
From the beginning, the unrelenting flames proved this was going to be a battle.
"The fire rapidly extended to the third, fourth, fifth and sixth floors, involving approximately 12 apartments," said FDNY Chief of Fire Operations Kevin Woods.
The fire pushed a fifth alarm, and just when there seemed to be a lull - and it looked like New York's Bravest had the upper hand, suddenly, they had to scramble.
Firefighters and medics rushed into the building - one of their own took a nasty fall, the FDNY says, while backing down the stairs.
"Stepped right into a window and then down about 40 feet of a shaft behind the building," said FDNY Commissioner Robert Tucker.
His fellow firefighters stood around the stretcher as he was wheeled to the waiting ambulance.
The seriously injured firefighter was working a hose inside - among first responders looking for pockets of fire and trapped residents - and maybe he had an angel on his shoulder.
"We were blessed today because we had the fire department physician on scene as well as the elite rescue medics at the location. So once the firefighters were able to bring our brother out, they were able to start immediate treatment and transport him to the hospital," said FDNY Chief of EMS Operations Michael Fields.
The firefighter was taken to Harlem Hospital where he is now in stable condition. Three other firefighters suffered minor injuries as well as five residents of the 145th Street building, who were also hurt.
Officials say at least 40 tenants are displaced - including Ester Enofe.
"If you stand on the other side of the building, I can see my apartment destroyed," Enofe said.
The cause of the fire remains under investigation.
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