South Korea's Joint Chiefs of Staff confirmed on Friday that in the early hours of July 18th a man surnamed Kim, who defected to the South in 2017, was spotted walking up to a pavilion on Ganghwa-do Island in Incheon after getting out of a taxi.
The man has been caught on the military's closed-circuit television moving towards a waterway which, the military says had not been monitored carefully during routine border inspections.
The military confirmed that one of the metal fences installed along the waterway had a gap of around 30 to 40 centimeters as a result of not being properly maintained since April.
It is presumed that this is how the defector was able to pass through the metal bars and barbed-wire fence.
The defector was spotted five more times during which he swam from the South to the North buoyed by tidal currents flowing in from the west to the east.
He was spotted leaving Ganghwa-do at around 2:46 AM then passing waters near Gimpo before surfacing at the North's Tanpo at around four AM on July 18th all in the space of about two hours.
The South Korean military acknowledged its failure to identify him as a person crossing the border as he blended in with other floating objects.
"The military recognizes the severity of what has happened. Various measures will be set up starting with increasing security levels in vulnerable areas such as the waterway. We'll also raise the operability of surveillance equipment as well as the level of expertise of those managing the equipment."
A two-star Marine Corps general commander of the Marine Corps' 2nd Division in charge of border security at the area is being relieved of his duties due to the security failure.
Kim Ji-yeon, Arirang News.