Investigators are looking into a fire/explosion at the Arcelor Mittal steel plant in Steelton.
Officials said one of the buildings ignited and exploded Sunday afternoon.
People reported seeing a fireball and smoke towering above the plant.
Emergency officials worked quickly to contain the fire.
UGI officials said there was a break in a hanging fuel line. Natural gas filled the building, it exploded, and collapsed.
No one was injured.
Officials said it happened in a building that workers use to shower and change. Since it was a weekend around 1:00 p.m., no one was even in the building at the time.
"Thank God that the building was empty. Because if it was a Monday morning or in the middle of the week changing a shifts and it was loaded with guys taking showers or whatever maybe we would've had some problems," said Steelton Mayor, Tom Acri.
"Our department trains really closely with Arcelor Mittal here their safety department so we're pretty well versed in how it operates," said Steelton Fire Chief, Stephen Brubacher.
UGI officials said there were fluctuations in natural gas distribution at the plant right before the accident happened, and they had workers en route when the building exploded.
All entities involved are working to try and figure out exactly what happened.