BROOKLYN - Fire investigators say a 5-year-old boy playing with a lighter set a deadly fire that swept through the top floors of a four-story Brooklyn building last night, killing his father and two of his siblings.

The fire was reported just after 5:30 p.m. on Putnam Avenue. About 60 firefighters battled the fire, which was brought under control about an hour later.

A police spokesman says the boy's 62-year-old father and 14-year-old sister were discovered on the top floor and pronounced dead on arrival. The third victim, a 3-year-old girl, was taken to a hospital where she was pronounced dead.

The fire marshal says flames erupted while the young boy was playing with a lighter and set a mattress on fire. Officials say instead of calling 911, the family attempted to pull the mattress down the staircase, but it got stuck.

Fire officials say at least three people were hospitalized, including one in critical condition. Two firefighters also suffered minor injuries.

FDNY: 3 killed, 7 injured in Bushwick fire