'A sad day': Philadelphia firefighter dies after building collapse traps 6 people

A Philadelphia firefighter died after a Saturday morning fire led to a building collapse, trapping six people under the rubble, fire officials said.

Lt. Sean Williamson, a 27-year veteran of the department, was pronounced dead at the scene of the fire, the Philadelphia Police Department said.

"It's a sad day for the Philadelphia Fire Department," Craig Murphy, 1st Deputy Fire Commissioner, said at a Saturday news conference. "Unfortunately, our department lost a member bravely fighting a fire and caught in a building collapse."

Williamson, 51, was "one of our most experienced lieutenants," and "highly respected throughout our department," Fire Commissioner Adam Thiel said Saturday. He was also a veteran of the Marines.

"I’m almost speechless. I’m not done crying," Thiel said. "We’re going to be there for Lt. Williamson’s family, his colleagues, his sisters and brothers with the Philadelphia Police Department."

Fire crews responded to the fire at a commercial building around 2 a.m. Saturday, Murphy said. What initially appeared to be a "pretty routine fire" progressed into a "total collapse" of the building by around 3:30 a.m., he said.

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Six people – a building inspector and five firefighters – were trapped in the building during the collapse, Murphy said.

Four of the firefighters and the inspector were taken to a hospital, and the inspector has since been released, he said.

Two firefighters were still hospitalized Saturday afternoon in "pretty serious condition," Thiel said.

Murphy described the collapse as a "lean-to/pancake collapse" with a lot of "void spaces" where people could have been trapped. Authorities were investigating the cause of the fire and collapse, he said.

One person jumped from the second floor of the building to avoid being trapped, Murphy said. Others were speaking with rescuers and tapping on debris to help crews identify where they were.

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Murphy said he knew Williamson and asked the public to pray for the department and the firefighter's family, calling the incident "a catastrophic accident that really hurt our department."

"People are just starting to decompress because we just finished up pulling our brother out of this place," Murphy said. "...It's going to be a rough few weeks."

Philadelphia Mayor Jim Kenney said on Twitter that he is grieving with the fire department and the City of Philadelphia, "who lost one of our own in the line of duty today."

Flags in Philadelphia will be flown at half-staff for 30 days to honor Williamson, the mayor's office said.

Contributing: Jeanine Santucci

Contact News Now Reporter Christine Fernando at cfernando@usatoday.com or follow her on Twitter at @christinetfern.

This article originally appeared on USA TODAY: Philadelphia firefighter dies in building collapse that traps 6