Fire officials say a New York City blaze that killed three people was started by a 5-year-old playing with a lighter.
The fire started Monday on a mattress that was tossed into an apartment building stairwell in Brooklyn.
A 14-year-old girl and a 3-year-old girl were killed along with a 62-year-old male relative. They were found on the top floor of the four-story building.
It's unclear if the mattress blocked their way out.
Police say a man remained in critical condition Tuesday. Three other building occupants and two firefighters suffered less severe injuries.