Five workers were killed and 11 injured on Thursday, March 14 when a storage tank exploded at a chemical plant in South Korea, firefighters said, according to AFP.

The tank, containing inflammable material, exploded around 19:00 (1200 GMT) at a Daelim Industrial plant in the southern coastal city of Yeosu.

"It did not start a fire and an investigation is under way," a firefighter told AFP.

Yonhap news agency said the workers had been engaged in welding when the tank storing the plastic polyethylene exploded.