Two workers were injured Tuesday morning in an explosion at a chemical plant in Hasaki, Ibaraki Prefecture, police and firefighters said.

The plant is operated by Daikin Industries Ltd., which makes air conditioners.

Fumiko Omura, 23, fractured her left shoulder, while Mitsuharu Hikawa, 41, sustained minor injuries to his forehead in the blast, which took place around 8 a.m., police said.

According to police and plant officials, the blast emanated from high-pressure gas-producing equipment used to extract impurities from ethylene tetrafluoride, the basic ingredient of fluorocarbon resin.

Police said combustible gas apparently caught fire and triggered the blast.