HOHHOT - Fire fighters on Sunday morning put out the blaze in a chemical plant in North China's Inner Mongolia autonomous region, which has caused one dead and three others injured.

The accident happened around 5 pm Saturday at Inner Mongolia 3F Fluorochemical Co Ltd. in the city of Fengzhen. A huge amount of flammable gas has been leaked after the chemical plant caught fire and exploded.

Some tanks containing VDF gas, a flammable and narcotic gas, on the ground floor of the plant's high-rise workshop caught fire. Fire fighters rescued three injured workers trapped in the flames, and evacuated other workers out of the building.

Firemen are still clearing embers to prevent secondary explosions.

The plant, located in the city's industrial park, is 10 km away from the city proper, and the nearest residential area is 3 km away.

An investigation into the cause of the blast is under way.