Military officers carry out security checks near a remote South Korean border outpost

These soldiers are looking for one of their own.

A conscript who's gone on the run after killing five of his fellow unit members, and injuring seven others.

Authorities have so far given few details about the incident, but they say they believe the soldier is armed with firearms and grenades.

(SOUNDBITE) (Korean) SOUTH KOREAN DEFENCE MINISTRY SPOKESMAN KIM MIN-SEOK SAYING:

"Regarding the soldier, we're conducting a search and deterrence operation to arrest him quickly and prevent more accidents."

All able-bodied South Korean men must serve about two years under a conscription system, aimed at deterring aggression by North Korea.

Though infrequent, there have been previous cases of soldiers, who have been under stress, opening fire on other unit members.