Firefighters say they were called to 327 E. 93rd Street between First and Second Avenues, just after midnight.
The fire broke out on the third floor of the five story building.
Firefighters from Engine 53 were first on the scene, and 50 firefighters were on the scene battling the fire until they could get it under control.
"Fire department units arrived, they stretched hose lines to the third floor to extinguish the fire. They performed searches in the building, on the fire floor, and the floors above," said one fire official.
"I looked out the kitchen, and outside was full of smoke," said Guertin, 35, who said he fled to the roof and climbed to the building next door.
The victims were longtime residents of the East 93rd Street building, building manager Glen Fogel said. Their names were not released.
Authorities haven't determined what caused the blaze, which left two firefighters with minor injuries, but they believe smoking in bed was a factor.
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STORY BY: Eyewitness News reporter Thalia Patillo
WEB PRODUCED BY: Scott Curkin
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