Kolkata: At least 25 workers were seriously injured Thursday in a gas pipeline explosion at the IISCO Steel Plant (ISP) in West Bengal, police said.

The incident took place in Burnpur in Burdwan district, about 210 km from state capital Kolkata.

"At least 25 people have been hospitalised with serious injuries following an explosion in a gas pipeline in ISP. The condition of seven injured is said to be critical. We are looking in to the cause of the explosion," said a police officer.

The injured have been admitted to the Burnpur IISCO Hospital.