At least one person remains unaccounted for while dozens have been injured following an explosion at the U.S. Steel Clairton plant on Monday.

First responders were alerted to the incident just before 11 a.m.

Others were trapped under rubble, with emergency workers on site trying to rescue them, according to The Associated Press.

Sources relayed to KDKA-TV that the explosion occurred inside the “reversing room” of the 13/15 battery. The room acts as a mechanical regulator, making sure the coal bakes evenly in the oven.

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Multiple people have been injured after an explosion at the U.S. Steel Clairton plant on Monday.

KDKA-TV

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Photo Credit: Breathe Cam

UPMC officials confirmed to KDKA-TV that they have received two patients at UPMC Mercy Hospital. 

An Allegheny Health Network spokesperson also confirms that “multiple AHN hospitals are receiving inbound patients.”

At least five patients were transported to Jefferson Hospital, one patient was transported to Allegheny General Hospital and another patient was hospitalized at Forbes Hospital.

Mayor Richard Lattanzi spoke with KDKA-TV after the incident.

“The mill is such a big part of Clairton. For anyone that works, how old or young you are, you have to work every day, you need to go home healthy, and some people are not going to see the same husband or son or somebody that’s working the mill. It’s just a sad day for Clairton,” Mayor Lattanzi said.

Pennsylvania lawmakers react to explosion

Gov. Josh Shapiro and Lt. Gov. Austin Davis issued statements on social media, saying the administration is actively in touch with officials in Clairton. The Pennsylvania Emergency Management Agency and the Pennsylvania State Police have offered assistance.

Sen. John Fetterman (D) confirmed that at least one person remains unaccounted for.

“My team and I are tracking this explosion and waiting for more information. For those in the area, please listen to local officials and avoid the area,” Sen. Fetterman said. “Keeping those injured and all who are impacted in my thoughts right now.”

Allegheny County Health Department “actively monitoring” situation

The Allegheny County Health Department is advising residents within one mile of the plant to remain indoors, close all windows and doors, set HVAC systems to recirculate, and avoid activities that draw in outside air, such as using exhaust fans. 

The health department’s air quality monitors have not detected levels of PM2.5 and So2 above federal standards, the department said in a media release.

This is a developing story. Please check back for updates.

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