Six workers dead in storage tank explosion at South Korea chemical plant

Firefighters looking through debris at the Hanwha Chemical plant in the south-eastern city of Ulsan, South Korea, on July 3, 2015.
Firefighters looking through debris at the Hanwha Chemical plant in the south-eastern city of Ulsan, South Korea, on July 3, 2015.PHOTO: EPA

SEOUL (AFP) - Six South Korean workers were killed on Friday when a waste water storage tank exploded at a chemical plant in the industrial city of Ulsan, a fire official said.

The blast occurred when the workers were carrying out welding work on the tank at the Hanwha Chemical Co. plant, which produces polyvinyl chloride, an Ulsan fire station spokesman told AFP.

"Gas from the waste water which had accumulated inside the tank was apparently ignited by the welding torch," he said.

An investigation was under way to determine whether the blast was caused by negligence.

Four workers were initially found dead at the scene, and rescuers later retrieved the bodies of two others while sifting through the mixture of debris and toxic waste water.