An explosion ripped through a steel plant in Pittsburgh leaving multiple people injured and others trapped.

Workers remain stuck under rubble at Clairton Coke Works in Pennsylvania, a raw coal processing facility, after the blast on Monday, officials said.

A fire initially broke out at the plant around 10.51am local time (3.51pm UK), according to Allegheny County Emergency Services. Five people have been taken to hospital.

The explosion sent a large column of black smoke billowing into the air visible for miles around.

A local told CNN that the explosion felt like an “earthquake”.