The blaze broke out at about 2:10 p.m. inside a two-story home at 112-16 208th Street in the Queens Village section and later jumped to a neighboring building, officials said. They managed to bring a 2-year-old and someone else from the attic where they had been trapped, he said.
Officials said five people have died. "They're wooden-frame homes and they are - they burn rapidly", Nigro said about the fast-moving nature of the fire.
The blaze ran through three alarms and burned for almost two hours before being declared "under control" around 4:30 p.m., according to the FDNY.
Two firefighters were hurt, but the injuries weren't critical, officials said.
There was no immediate theory on what started the blaze, but Nigro said there appeared to be no explosion, even though witnesses reported hearing loud booms. Several children were among the dead, police said.
Firefighters responded within minutes but couldn't save five people, including three children, who were inside.
Mayor de Blasio was visibly moved as he spoke to reporters just yard away from smoldering scene after the fire was under control.
The fire spread from the two-story house to another home, the FDNY said. "I was just praying for them".
"They were screaming, 'Get the kids out!"
Although they valiantly fought the fire, they couldn't rescue anyone from inside, he said. "There were so many firefighters out there", said Tiasha Johnson, who lives in the neighborhood.
Neighbor Denise Coleman told the Daily News of NY that people were screaming to get the children out. "I've never seen anything like it".