City officials say 42-year-old Lieutenant Matthew LeTourneau was pinned under debris inside the home when it collapsed.
Three Philadelphia firefighters were reportedly injured while battling a rowhome fire in North Philadelphia on Saturday.
"Our hearts are breaking", Thiel said.
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Two firefighters were injured and taken to the hospital where they were treated and released.
The fire department responded to a home on the 800 block of North Holly Street just after 3:30 a.m.
He was rescued by fellow firefighters and taken to the hospital. The 11-year-veteran was pronounced dead there a short time later. Their injuries were not considered life-threatening. Reports indicate a person found inside the home had died. The fire marshal's office is investigating the cause of the fire.
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In 2010 he was awarded a unit citation and he received a commendation for his service during the World Meeting of Families in 2015. He was a 1993 graduate of Cardinal O'Hara High School and held an associate's degree in fire science from Delaware County Community College.
Democratic Mayor Jim Kenney said the city will "be there for (LeTourneau's) family forever".
Funeral arrangements for Lt. LeTourneau have not yet been announced.
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