Al-Ashraf Khalil, the building's owner, and Isaam Jaghama set the three-story property on fire in June 2022 so that Khalil could profit by filing an insurance claim.
Building owner accused of setting fire that led to Philadelphia firefighter's death
Lieutenant Sean Williamson was killed and five other first responders were injured when the building collapsed.
Eight people were safely evacuated from the apartments after the fire broke out, but the building collapsed after the blaze was brought under control and trapped Williamson inside.
He was pronounced dead at the scene.
"Arson is a dangerous deadly crime," said Eric DeGree, Special Agent in Charge of the ATF Philadelphia Field Office. "In this case two families with children had to run for their lives, four responders were buried alive, and a firefighter was killed."
Khalil faces a mandatory minimum sentence of 17 years in prison and a maximum possible sentence of life in prison.
Jaghama faces a mandatory minimum sentence of seven years in prison and a maximum possible sentence of life in prison.
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