The collapse occurred on the 1200 block of Pollett Walk at the new Science Education and Research Center building that is currently under construction.
"This was a very serious situation," Philadelphia Fire Commissioner Lloyd Ayers said.
Around 1:30 p.m. Thursday, right in the center of the Temple University campus, the corrugated upper floor of the 8-floor building under construction collapsed. People, including workers on other campus projects nearby, described hearing a very loud crumbling noise then cries for help.
"When we heard the noise, we all came out to see what's going on," store owner Joe Kobabcy said.
"We heard this loud boom and as we came to the door, we see the building had collapsed," Temple University employee Lorraine Bryant said.
"We're working on the building down the street and seeing something like this happen, you feel bad for everyone that's working, for sure. But somebody did something they weren't supposed to, looks like for me," construction worker Rob Monahan said.
Fire crews and paramedics rushed to the scene. They found one construction worker seriously injured and five other construction workers trapped.
"We had heavy rescue, went up to that location, they assessed the situation as far as how safe it was to start the operation. They did start the operation. We got our paramedics up to care of the injured worker that was down," Ayers said.
Paramedics worked to stabilize the injured construction worker. He was brought down to the ground level along with his five coworkers on a working elevator on the other side of the construction project.
"The building has been shut down. The construction site has been shut down. We'll be working with the city to determine what went wrong inside the building immediately," Temple University spokesperson Ray Betzner said.
According to the Temple website, "A new $137-million facility will be constructed on the open space between the Engineering Building and Gladfelter Hall and will provide advanced technology and modern lab spaces for student learning and research."
The architect of the building, according to the website, is ARC/USA Architects.
The website says the proposed size of the building is 250,000 square feet.
The building's expected completion date is June 2014.