By the time the scene was secure, two people were dead and more than 10 others were injured, including one who spent hours trapped in rubble left Monday by the blast that was powerful enough to shake nearby homes.

The body was discovered after a search operation which stretched into the evening at the US Steel Clairton site outside Pittsburgh. Local police earlier confirmed that one other person had died and 10 others were injured in a large explosion which destroyed part of the plant.