Nine children and three adults were confirmed dead in the Jan. 5 fire that started on the second floor and quickly traveled to the third floor of the N. 23rd Street building, authorities said.
The 12 victims died of smoke inhalation, according to the Philadelphia Department of Public Health’s Medical Examiner’s Office.
"We are almost certain that the Christmas tree on the second floor was the item that was first ignited. We are near certain that what ignited that fire, was a lighter [found nearby]," Philadelphia Fire Commissioner Adam Thiel said during a press conference Tuesday.
"The only surviving person on the second floor at the time the fire was ignited was a 5-year-old," he added.
In interviews with fire investigators and other media outlets, the five-year-old boy allegedly stated that he was playing with a lighter when the fire started.
"We are left with the words of that 5-year-old child, that traumatized 5-year-old child, to help us understand how the lighter and the tree came together with tragic consequences because we have disproved any other theories," Thiel said.
Investigators found six inoperable smoke alarms in the building, Thiel said. Most had been removed from the ceiling.
There was an additional smoke alarm in a shared basement that did go off, but it went off late, he added.
All smoke detectors were operating properly during inspections completed by the Philadelphia Housing Authority in April 2021 and May 2021, according to PHA representatives.
As of now, the fire has been classified as incendiary rather than accidental, according to Thiel.
"We believe there was some type of human intervention to bring the ignition source to the first item ignited," Thiel noted.
The "complex and multifaceted" fire investigation will take time to complete, Mayor Jim Kenney previously said.
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