After being hit five times, he was recovered by South Korean and UNC guards there and airlifted to a hospital south of Seoul. He's alive but unconscious.

In press briefings, South Korean defense officials have called him a North Korean soldier, saying he was clad in a Korean People's Army uniform.

But the UNC officially describes him as an "individual" presumed to be a KPA soldier.

There's a heated controversy over whether the South's guards should have returned fire. They focused on rescuing the defector, refraining from using force in accordance with the JSA rules of engagement set by the UNC, according to the defense authorities.

Also at issue is the possibility of at least a North Korean soldier having crossed the border line with no specific mark while running after the defector.

The Armistice Agreement stipulates that "No person, military or civilian, shall be permitted to cross the military demarcation line unless specifically authorized to do so by the Military Armistice Commission."

According to multiple sources who viewed related CCTV footage, one of the North Korean soldiers flinched apparently after recognizing the trespass.

The UNC initially promised to make public a clip on Thursday showing what happened there at that time but it indefinitely postponed the release.

The command said it will instead "release additional details and material once that investigation is complete."

Even if the North's violation of the Armistice Agreement is confirmed, the UNC has no means to punish it.

The first measure will be lodging a formal protest with the North but the problem is how amid a lack of communication channel.

No talks between the KPA and the UNC have been held since March 2009.

The UNC proposed consultations between general-grade officers after the North's deadly torpedo attack on a South Korean warship near the Yellow Sea border in 2010 but the KPA rejected it.

An alternative is that a UNC official reads a protest message via loudspeaker or place a relevant statement along the MDL and wait for the North's guards to pick it up.

Furthermore, Pyongyang declared the Armistice Agreement invalid in the wake of its third nuclear test in early 2013.

It means the UNC has no realistic tool to use other than symbolic gestures.

Established a month after the outbreak of the 1950-53 Korean War, the US-led UNC is a signatory to the agreement also signed by North Korea and China.

It's tasked with overseeing the implementation of the agreement and deterring the North's aggression. (Yonhap)