SEOUL, Korea, Republic Of -- Surgeons treating a North Korean soldier who was severely wounded by gunfire while escaping to South Korea this past week removed dozens of parasites from his body, including presumed roundworms that were as long as 27 centimetres (10.6 inches).

The unarmed soldier, whose name and rank have not been disclosed, defected to the South on Monday by driving a military jeep near a line that divides the Koreas at the Joint Security Area and then rushing across it under a barrage of bullets. Hospital officials said Saturday that it was too early to tell whether he will make a recovery.

While treating the wounds, surgeons found the large parasites, which may be reflective of poor nutrition and health in North Korea's military. Doctors measured the soldier as being 1.7 metres (5.6 feet) tall, but weighing just 60 kilograms (132 pounds).

"I spent more than 20 years of experience as a surgeon, but I have not found parasites this big in the intestines of South Koreans," Lee Cook-jong, who leads the soldier's medical team, told reporters.

Lee is a famous trauma specialist who was hailed as a hero in 2011 after conducting life-saving surgeries on the captain of a South Korean freighter ship who was shot during a rescue mission after being held by Somali pirates.

While the North Korean soldier's vital signs were stabilizing on Saturday, he continued to remain unconscious and relying on a breathing machine. After consecutive surgeries to repair internal organ damage and other injuries, no further surgeries are planned as of yet, said Shin Mi-jeong, an official at the Ajou University Medical Center near Seoul.

South Korea's military said four North Korean soldiers used handguns and AK rifles to fire about 40 rounds at their former comrade, who was hit at least five times. He was found beneath a pile of leaves on the southern side of the Joint Security Area, and South Korean troops crawled there to recover him. A United Nations Command helicopter later transported him to the Ajou hospital.

It remains unclear whether the North Koreans chasing the soldier fired at him even after he crossed into the southern side of the border, which would be a violation of an armistice agreement that ended the 1950-53 Korean War. The U.N. Command, which is investigating the incident, postponed a plan to release video footage of the soldier's escape on Thursday.

The Joint Security Area is jointly overseen by the American-led U.N. Command and by North Korea, with South Korean and North Korean border guards facing each other only meters (feet) apart. It is located inside the 4-kilometre (2 1/2-mile) -wide Demilitarized Zone, which forms the de facto border between the Koreas since the Korean War.