U.S. Steel's Clairton Coke Works — long flagged for safety and environmental concerns — is under fresh scrutiny after an explosion killed two workers this week. The big picture: Once a defining part of the Pittsburgh region's economy,

The U.S. Steel plant in Clairton, Pa., where an explosion killed two workers and injured 10 on Monday, has a history of maintenance issues, explosions and environmental violations.

A day after a deadly explosion rocked the Clairton Coke Works facility, Allegheny County officials confirmed that two men were killed and five others remain hospitalized in critical but stable condition as authorities continue to investigate the incident alongside federal and local partners.