One man was killed and another injured late Sunday after an explosion rocked a Kyushu Steel Corp. plant in Takeo, Saga Prefecture, police said.
The police said the explosion took place at around 11 p.m. Sunday in the plant's basement.
The blast killed a 28-year-old employee who was investigating the cause of smoke coming from the basement area, the police said.
Injured was a 45-year-old employee who got burned while trying to rescue the man.
More than 10 workers were at the plant when the accident occurred, but no other injuries were reported.
Police think a leaky hose used to provide oxygen to a ground-level electric furnace in a basement-level machine room triggered a fire that led to the blast.
The steel-maker, headquartered in Fukuoka Prefecture, has 167 employees, according to its website.