South Korean Defence Minister Song Young-moo said it was the first time North Korean soldiers had fired towards the South's side of the JSA, prompting complaints from some lawmakers that the South's military should have returned fire.
The wounded soldier required emergency evacuation, the statement said, after defecting from a North Korean guard post at the Joint Security Area (JSA) on the heavily-guarded border between the two countries.
The United States has said that all options, including military, are on the table to deal with North Korea, although its preference is for a diplomatic solution. In Monday's incident, it wasn't known if the North continued firing after the defector was officially in the southern part of the Joint Security Area. "Trump, during his visit, laid bare his true nature as destroyer of the world peace and stability and begged for a nuclear war on the Korean peninsula", a North Korean official said in a statement on Saturday.
South Korea's military has strengthened vigilance in the wake of the incident and remains prepared for any situation, the JCS said.
China will send a special envoy to North Korea on Friday, the state-run media said today, days after US President Donald Trump visited Beijing and urged his Chinese counterpart Xi Jinping to act fast to rein in Pyongyang.
More than 30,000 North Koreans have defected to the South since the end of the 1950-53 war, but it's rare for soldiers to flee across the DMZ, much less the JSA. An estimated 1,000 people flee Kim Jong Un's volatile regime each year, but going through the DMZ - fortified with land mines, barbed wires and machine guns - have been extremely rare because of the unsafe conditions.
The soldier's successful escape makes only the fourth defection by a North Korean soldier through the DMZ in the last three years, the BBC reported.
He received gunshot wounds to the shoulder and elbow from North Korean forces while defecting. They stand only several yards away from tall South Korean soldiers wearing aviator sunglasses and standing motionless like statues. It is located inside the 4-kilometer-wide (2 1/2-mile-wide) Demilitarized Zone, which forms the de facto border between the Koreas since the Korean War. More than a million mines are believed to be buried inside the zone.
The North Korean ambassador accused the council of "turning a blind eye to the nuclear war exercises of the United States who is hell bent on bringing a catastrophic disaster to humanity".
It marks the first massive joint drills since Seoul and Washington agreed last month to enhance rotational deployments of USA strategic assets to curb North Korea's nuclear and missile threats.
The Joint Security Area was the site of some bloodshed during the Cold War but there hasn't been major violence there in recent years.
The soldier was airlifted to a hospital south of Seoul after he was found bleeding under a pile of leaves Monday in the truce village of Panmunjom, the only point in the DMZ where both sides come face to face.
The presence of three U.S. aircraft carriers off the Korean Peninsula is pushing the region closer to nuclear war, according to a North Korean letter to the United Nations secretary-general, CNN reports.