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.

Multiple explosions at a steel plant near Pittsburgh have killed two people and left 10 others injured on Monday, according to authorities. Video captured a massive black plume of smoke rising from the U.

A fire Monday at the US Steel mill, 20 miles south of Pittsburgh, hurt 10. Residents within a mile are advised to stay indoors.