Two workers were killed and another left in critical condition after a factory explosion Saturday morning in north China's Hebei Province, said local authorities.

The fan room at the Hebei Bohai Coking Co., Ltd. exploded at 11:45 a.m., setting the room on fire in Cangzhou City, according to the municipal Work Safety Administration spokesman.

The injured worker is being treated in hospital, said the spokesman.

The fan room equipment was being repaired prior to the blast occurring.

The fire has since been extinguished and police have begun an investigation of the incident.