In the Korea Times, historian Robert Neff has a good article published about the 1982 defection of Private First Class Joseph White to North Korea that I recommend everyone read:
On August 28, 1982, at about 2 a.m., the sound of a single gunshot shattered the silence of the Panmunjeom region of Korea’s Demilitarized Zone (DMZ).
Korea Times
Gunfire along the DMZ was not uncommon, and while it was alarming, none could have imagined that it signified the unthinkable ― the defection of an American soldier to North Korea.
The incident occurred at Guard Post Oullette, one of the most forward American positions at that time in South Korea. PFC Joseph T. White, a member of the 1st Battalion of the 31st Infantry Regiment, was alone at his post when he shot off the lock of one of the gates leading into the 2.5-mile-wide DMZ, and made his way into one of most heavily fortified and mined zones in the world.
White was equipped with an M-16 with an attached grenade launcher, ammo, night-vision goggles, operating instructions for radio equipment and some unclassified information on radar and sensor systems, but all of these were left behind except his weapon and ammo.
You can read more at the link.