PHILADELPHIA (KYW Newsradio) — A firefighter is dead and two others are in critical but stable condition after a building collapse in Philadelphia's Fairhill neighborhood trapped several people early Saturday morning, according to fire officials.
Deputy Fire Commissioner Craig Murphy said a fire broke out around 2 a.m. at a pizza restaurant on the corner of 3rd Street and West Indiana Avenue.
After the fire was put out, the building of apartments above the restaurant collapsed at 3:24 a.m., trapping five firefighters and an inspector from the city's Department of Licenses and Inspections.

Four firefighters were rescued from the debris.
Officials identified them as Dennis Daly, Robert Brennan Jr., Lt. Clarence Johnson and Fire Marshal Lt. Sylvester Burton.
All four were taken to Temple University Hospital. Daly and Brennan were listed in critical but stable condition.
One firefighter, identified as 51-year-old Lt. Sean Williamson, died at the scene. Murphy said he was a 27-year department veteran.
Numerous firefighters were at the scene as the rescue effort unfolded, and some were seen hugging or wiping tears from their eyes, multiple news outlets reported.
Murphy said he and his crew were trying to process the loss of one of their own.
“We just finished up pulling our brother out of this place,” he said.
“You can’t predict this. This was just a catastrophic accident that [has] really hurt our department.”
An inspector from the Department of Licenses and Inspections was also caught in the collapse. He was treated for his injuries following his rescue, then released.
Kareem Hampton, who works for an emergency services company and says he just barely escaped, himself, said he witnessed the collapse that killed Lt. Williamson.
“As the fire marshal got done with his investigation, I was walking into the house with the homeowner, obviously, because I deal with insurance companies. And, literally, as soon as I stepped through the threshold, the building started to collapse,” Hampton said.
“Another company that does the same thing I do said, ‘Yo, back up from the building!’”
He said the lieutenant then jumped from the back railing of the second story.
“You can see his legs sticking out. We’re screaming his name, firefighter down, we’re trying to get all the debris off of him,” Hampton said. “He wasn’t moving, honestly, but he was conscious. He did respond back to us.”
And then, Hampton said, he was told to back away.
ATF's National Response team launches investigation
Agents from the ATF’s National Response Team are inspecting the property at North Third Street and Indiana Avenue in Fairhill, and aiding Philadelphia officials with an investigation into what started the deadly fire and subsequent building collapse.
According to city records, the property had several open violations, including one for an inoperable fire alarm and another for a missed fire alarm certification.
The ATF routinely assists fire marshals with their investigation. They sometimes use a 3D scanner to determine where the spark may have ignited. The specialized equipment helps fire officials see if there were any incendiary materials on site, and also helps test debris from the scene to determine if the cause of the fire could be arson.
Remembering Lt. Williamson
Williamson was a father, a veteran of the Marine Corp, and was known as a go-getter. He worked for Rescue 1, a specialized fire company and was also part of the state’s Task Force 1 which would help in disasters.
The Philadelphia Fire Department has announced a series of memorials for Lt. Sean Williamson, who died during a building collapse in Fairhill on Saturday.
People can attend public viewings on Sunday, June 26 from 6 to 9 p.m. and on Monday, June 27 from 9 to 11 a.m. at Epiphany of Our Lord Church near the corner of 11th and Jackson streets in South Philadelphia.
Gov. Tom Wolf has also ordered the commonwealth flag to be flown at half-staff in Philadelphia County through Friday and on the day of Lt. Williamson's funeral.
A funeral Mass will happen on Monday at 11 a.m. at the church, followed by a procession going eastbound from the corner of 22nd and Hunting Park Avenue to Broad Street, then traveling south on Broad to Stolfo Funeral Home near the corner of South Broad and West Shunk streets.
Find full details of arrangements planned for Lt. Williamson here.
KYW Newsradio's Justin Udo contributed to this story.