Officials probe cause of blast at Pa. coke plant

CLAIRTON, Pa. (AP) — Investigators are searching for clues to what caused an oven to explode at a U.S. Steel plant near Pittsburgh, injuring 20 workers.

Officials say the powerful blast in a coke oven at United States Steel Corp.’s Clairton Coke Works happened around 9:30 a.m. Wednesday.

Most of the injured workers are being treated for burns; one suffered chest pains.

Allegheny County Emergency Services Chief Bob Full says it’s a miracle that anybody walked away from a blast that bent steel beams and destroyed block walls.

Union and company officials are trying to figure out exactly what caused the explosion.

A spokeswoman also says the Occupational Safety and Health Administration has sent a team of investigators to the site.