When the war broke out, President Kim Il Sung took a step to move a munitions factory in Pyongyang to a tunnel in Kunja-ri, Songchon County, South Phyongan Province.

True to his noble intention, the workers of Kunja-ri launched a struggle for producing weaponry in the do-or-die spirit.

Receiving an order of the President to produce 700 stands of submachine guns in a week during the strategic temporary retreat, they organized a death-defying corps for the weaponry production. Whenever electricity was cut off due to the enemy's bombing, they processed accessories by turning the belt of lathes with hands and assembled submachine guns by lamplight and continued to test-fire weapons in the narrow tunnel. Even though the enemies came near the factory, the members of the corps did not stop their working and produced 750 stands of submachine guns at last.

When materials and explosive were out of stock, they carried those materials on their back from a place more than 40 kilometers off in one night and used the enemy's time bombs and unexploded bombs to ensure the steady production. They continued to work without rest and assembled the weapons while eating uncrushed maize and salt.

Their spirit of self-reliance, the revolutionary spirit of devotedly implementing the President's order, was recorded in the history of the great Fatherland Liberation War.