Allegheny County is increasing air quality monitoring after an explosion at a U.S. Steel plant south of Pittsburgh killed two people and injured more than 10 others

Regulators are temporarily stepping up pollution monitoring in the Mon Valley after a deadly explosion at U.S. Steel’s Clairton Coke Works on Monday sparked worry about the release of toxic gases. The

The health department began deploying mobile air units Thursday provided by Pennsylvania’s Department of Environmental Protection and Carnegie Mellon University. The units will travel around Clairton to test for dozens of hazardous air pollutants.

Allegheny County Emergency Services said a fire at the plant in Clairton started late Monday morning. Officials said they had not isolated the cause of the blast.

A devoted dad has been identified as one of the two steel workers killed from an explosion at a Pennsylvania steel plant on Monday, officials said.