Rescuers were continuing to search for one missing worker at the Clairton Coke Works more than five hours after mid-morning explosions rocked the Mon Valley plant. The blasts killed one person and injured 10.

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,

At least one person has died, one person remains unaccounted for, and at least 10 people have been injured following multiple explosions at the U.S. Steel Clairton plant on Monday.