Workers on the fifth and sixth floors of the under-construction Temple University science building in North Philadelphia were temporarily stuck after a partial collapse on a lower floor of the site, the city fire department said.
No injuries were immediately reported, according to a spokesman for the fire department, but live video of the scene from an NBC10 helicopter appeared to show someone on a stretcher attended to by firefighters.
The live television footage later showed the person being taken from the scene in an ambulance.
The collapse of a portion of the fourth floor of the building, which is 200 feet by 400 feet, near North 11th Street and Polett Block occurred at 1:17 p.m., Executive Fire Chief Richard Davison said.
No cause for the collapse was immediately known. The scene was cleared by emergency officials shortly before 2:30 p.m.
Check back for more details as they become known.