The fire broke out inside the building just before 6:40 a.m. Thursday on Avenue M in the Midwood section.
At least four people were hurt in the fire. A man was rushed to the hospital with life-threatening injuries.
The 30-year-old man is being treated for severe burns at Staten Island University Hospital North.
The other people being treated for injuries are all expected to survive.
Dramatic video showed firefighters entering the lobby and pulling out what appeared to be an e-bike that was engulfed in flames and blocking the stairwell. It is believed to be the property of one of the injured victims.
Multiple e-bike batteries were also apparently found on fire inside.
Neighbors applauded the FDNY and said they were heroes for stopping the spread as quickly as they did.
"The fire was raging, and all of the windows broken, and the fire was looped around to the roof and these brave men, they were just on the ladders, just going on... like this is their life," said witness Lillian Crespo.
Residents salvaged what they could and picked through the rubble. The Red Cross is helping them find places to stay.
Neighbors wonder how much of the damage could have been prevented, had the e-bike been used or stored more safely.
"This is not going to stop, everyone in this neighborhood has a bike and scooter, I mean everyone," Crespo said.
The FDNY has been adamant about e-bike safety education and it may be working.
There were 13 deaths from lithium-ion batteries this time last year, and so far this year, there has been one.
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