An explosion at an munition factory in Daejeon City has killed three workers.

The explosion coupled with a fire occurred at 8:42 a.m. Thursday at a manufacturing plant handling explosives operated by Hanwha Group.

Three people are confirmed dead; one quality inspection employee and two others serving in the assembly building. 

Fire authorities suspect the explosion likely occurred when substances used to ignite rocket fuel were being separated from a rocket propellant.

The police and fire officials are investigating the exact cause of the incident together with the Korea Electric Power Corporation and the Korea Gas Corporation.

The Daejon Regional Employment and Labor Administration has ordered the suspension of operations at the Hanwha plant.

The same factory which manufactures multiple rocket launchers reported an explosion in May last year in which five people were killed.