An extension cord overload caused the deadly fire in Hamilton Heights late Monday that killed a 15-year-old girl and injured at least 12 others.
Fire Department officials said on Tuesday that the blaze appeared to be suspicious at the time because investigators couldn't determine the source or cause.
Upon further investigation, however, Commissioner Daniel Nigro said the fire was found to have started on the first floor of the six-story building at 512 West 136th St.
Fire marshals now believe a power strip plugged into an extension cord placed under a large furniture piece triggered the four-alarm fire.
A series of tragic mishaps, Nigro added, led to the death of teenager Melisa Mendez. He explained the resident in the apartment where the fire started neglected to close the door, which hastened the fire's spread.
"Had that door been closed, the outcome would have been very different," Nigro said.
Ten firefighters were injured by the fire, two more seriously than the others. Two residents were also treated for minor injuries, officials said.
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