U.S. Steel says its preliminary investigation found that the blast happened after pressure built up while a gas valve was ...

Workers were heating coal and preparing for routine maintenance when an explosion rocked a U.S. Steel plant outside ...

Allegheny County is increasing air quality monitoring after an explosion at a U.S. Steel plant south of Pittsburgh killed two ...

Preparations for a routine maintenance task may have led to an explosion at a U.S. Steel coal-processing plant near ...

An explosion at a U.S. Steel plant south of Pittsburgh killed two people and injured more than 10 others. The CEO has vowed ...

Production at the facility could be affected for some time. Two of the plants six batteries of ovens were damaged in the ...

Authorities confirmed a second fatality after an explosion at the U.S. Steel Clairton Coke Works facility outside of Pittsburgh.

An explosion at a U.S. Steel plant near Pittsburgh left one dead and dozens injured or trapped under the rubble Monday, with emergency workers on site trying to rescue victims, officials said.

Officials provided an update on an explosion at a U.S. Steel plant near Pittsburgh, Pennsylvania, that left at least one ...