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.

The explosion took place at the US Steel Clairton Coke Works plant, located south of Pittsburgh, Pennsylvania.

Two people have died and 10 are injured following an explosion at a Pennsylvania steel plant on Monday, Allegheny County police said.