The explosion, followed by several smaller blasts, could be felt in the nearby community and prompted county officials to warn residents to stay away from the scene so emergency workers could respond.

One person has died, one person is unaccounted for and at least 10 are injured following an explosion at a U.S. Steel plant near Pittsburgh, Allegheny County Police Assistant Superintendent Victor Joseph said at a press conference Monday afternoon.

Workers were pushing coke out of huge ovens and preparing for maintenance when an explosion rocked a U.S. Steel plant outside Pittsburgh, a company executive said Tuesday, a day after the blast killed two workers.