FDNY Commissioner Daniel Nigro told reporters Sunday there were no fire escapes on the apartment building that went up in flames, but there were stairways for escape.
"The residents should know where the stairwells are and I think some of them could not escape because of the volume of smoke," Nigro said. "I believe there's 120 apartments in the building. There's a very large number of people right now who need a place to stay."
He added fighting the fire was a very difficult job for rescue crews on scene.
"Smoke and heat travel upward, that we know -- that's what happened here," Nigro said.
"It was a very difficult job for our members. Their air tanks contained a certain amount of air -- they ran out of air, many of our members -- and they continued working to try to get as many people out as they could."