An oil tank at a plant in the southeastern city of Ulsan exploded Monday morning, killing one worker and injuring another.

The tank exploded at a United Terminal Korea factory at around 11:20 a.m., after which one worker in their 30s was found with no vital signs following a fall.

The worker was later prounced dead at a hospital.

Another worker was transported to a hospital with a serious, but non-life threatening injury.

The company handles storage and transport of various liquid cargo and a unit of two workers was reportedly inspecting external oil tanks at the time of the explosion.

Fire authorities managed to completely put out the fire at around 2:19 p.m., some three hours after it started.

The labor ministry launched in investigation into possible violation of the Serious Accidents Punishment Act, while the Ulsan Coast Guard Station plans to investigate details of the accident.