One person died and two others sustained injuries and were taken to a hospital after an explosion Monday at Nippon Steel & Sumitomo Metal Corp.'s Yahata plant in Fukuoka Prefecture, according to the local fire department.

The man who was killed was in his 30s and was believed to be a worker at a Nippon Steel & Sumitomo affiliate. A man also in his 30s suffered serious burns, while one in his 20s received minor injuries, the authorities said. Their identities were not immediately known.

The explosion occurred at a subsidiary of Nippon Steel & Sumitomo, located inside the plant about 7 km west of the Kokura train station in Kitakyushu, when liquefied natural gas used in a furnace to harden steel caught fire, authorities said.

A caller who heard an explosion at the plant notified the fire department at about 1:15 p.m.

Authorities said they were continuing their investigation.