SEOUL — In November 2020, a North Korean ex-gymnast climbed undetected over 10-foot barbed-wire fences to get into South Korea. When the South belatedly discovered the breach, it began an extensive manhunt. The man was not found until the next day, half a mile south of the world’s most heavily armed border.
It was one of the South Korean military’s most embarrassing moments in years.
On New Year’s Day, officials say, the man humiliated the military again by making the trip in reverse, climbing the same fences and crossing the Demilitarized Zone to return to the North.
His extraordinary feat not only highlighted South Korean security flaws at the 2.5-mile-wide buffer zone, known as the DMZ, but raised the bewildering question of why someone would risk his life by crossing it twice. The DMZ is lined with barbed-wire fences, minefields and armed sentries. Few North Koreans who defect to the South do so by crossing it directly (most go through China), and it is even rarer for a defector to return that way.
“We are sorry for causing concerns to the people,” Gen. Won In-choul, the chairman of South Korea’s joint chiefs of staff, told lawmakers on Wednesday. “We will make every effort so there is no recurrence of similar incidents.”
At the same hearing, Defense Minister Suh Wook confirmed that South Korea believed the border-crosser was the former gymnast who defected in 2020. The government has not released his name, but other North Korean defectors have identified him as Kim Woo-joo, 29.
They said he had few friends, and his motive for going home was still a mystery on Thursday. Some lawmakers have speculated that he was a spy, but President Moon Jae-in’s government said it had found no evidence of that.
A series of lapses let him slip through the DMZ, said Lt. Gen. Jeon Dong-jin, who led the army’s investigation into the security breach.
He was first picked up by a military security camera about 1 p.m. on Saturday, as he was walking toward an area just south of the DMZ, in the eastern province of Gangwon, that is off-limits to civilians. A warning was broadcast over loudspeakers, but the military took no further action after the man seemed to change course and head for a nearby village.
Six hours later, he was climbing the first tall fence on the southern edge of the DMZ. Three cameras captured the scene, but a soldier on duty, who was monitoring real-time feeds from nine cameras on a single computer screen, missed it. Sensors on the fence triggered an alarm, but a first-response team ruled that nothing was amiss.
Hours later, in the dead of night, the military’s thermal observation devices detected the man deep inside the DMZ, on his way to North Korea.
Of the roughly 34,000 North Koreans who have defected to South Korea, 30 have mysteriously resurfaced in the North in the past decade. Some are believed to have been blackmailed into returning. Others have fled criminal charges in South Korea.
Still others are thought to have gone back because, after growing up in North Korea’s highly regimented, totalitarian society, they could not adjust to the hypercompetitive life of the South, where defectors are often treated like second-class citizens. What little is known about Mr. Kim’s life in the South suggests that he may fall into that category.
Fellow defectors say that Mr. Kim, like most North Koreans who come to the South, adopted a new name: Kim Woo-jeong. He appears to have had a hard life in both Koreas, according to officials and lawmakers who received briefings from military and intelligence officials.
Like all defectors, Mr. Kim was debriefed by the South Korean government upon arrival. He said he had fled the North to escape an abusive stepfather. At the time, Mr. Kim weighed barely more than 110 pounds; he stood just taller than 4-foot-11.
Crossing the North’s border with China — the usual route for refugees — had become nearly impossible because of the coronavirus pandemic. To keep the virus out, North Korea had greatly tightened its controls at that border, reportedly placing its guards under “shoot to kill” orders. Instead, Mr. Kim crossed the DMZ, where, South Korean officials said, his gymnastic skills helped him climb the tall fences.
In South Korea, his life seems to have been a difficult one.
He made few friends, officials said. He found work at cleaning services whose employees worked mostly at night in empty office buildings. He apparently never socialized with his neighbors. Since Sunday, when reports first emerged of his return to the North, no one in the South has come forward to say that they knew him personally.
Kang Mi-jin, a North Korean who lives in Seoul, said that a defector’s early experiences could be crucial. “It’s important what first jobs they find in the South and how they are treated here,” she said. “That’s where they learn whether their dream is supported by reality.”
Their first friends are usually fellow North Koreans, whom they meet during the government’s 12-week resettlement training program. Before the pandemic, when as many as 3,000 defectors were arriving every year, those classrooms were full. But with the North’s Chinese border locked down, only 229 North Koreans came to the South in 2020, the year Mr. Kim defected.
“He had few classmates and few friends,” said Ahn Chan-il, the leader of a defectors’ group in Seoul. South Korean churches, where many defectors have found communities, have been under restrictions during the pandemic.
If Mr. Kim was suffering from poverty and loneliness in the South, he was hardly the only defector who felt that way.
Nearly a quarter of North Korean defectors — six times the national average — are receiving government subsidies for basic necessities because they are in the lowest income bracket. Those among them who earn wages make 70 percent of the national average, according to a survey of 407 defectors conducted last year by the Seoul-based Database Center for North Korean Human Rights.
Thirty-five percent of those defectors reported experiencing depression and despair, and 18.5 percent said they had thought of returning to the North, mainly because they missed their families and hometowns, according to the survey.
One reason many unhappy defectors endure life in the South is that they can save money and send it to their families in the North through middlemen in China, who usually charge a 30 percent fee. But temporary jobs like the ones held by many defectors were among the first to be cut by employers as the pandemic raged.
Living alone in a tiny, $117-a-month apartment in northern Seoul, Mr. Kim received $418 a month in welfare support from the government. He rarely cooked and skimped on gas, water and electricity, and he had unpaid bills for rent and medical insurance, according to the South Korean news agency Yonhap.
“We help the North Korean refugees resettle when they first arrive, but we have been miserly in helping them find jobs and make their life here sustainable,” Park Soo-hyun, Mr. Moon’s senior secretary for public communications, said this week.
For some defectors, the transition to the South is like that experienced by a prisoner, released after many years, who cannot readjust to the outside world, said Lee Min-bok, a longtime North Korean refugee.
“They are strangers to the sudden freedom in the South, finding it more difficult than life in North Korea, which is essentially a prison,” Mr. Lee said. “The ostracism they feel in the South is not much different from the discrimination ex-prisoners suffer on the outside.”
The culture shock is especially hard for the few who cross the DMZ. Many defectors spend years living in China, which is far more open to the world than North Korea is. By the time they come to the South, they have some idea of what to expect.
As of Thursday, North Korea had said nothing about Mr. Kim’s return. It has often used returning defectors for propaganda, releasing videos and articles in which they describe a hellish life in the capitalist South.
Mr. Kim left few traces behind. At the fence where he crossed, investigators found thin footprints and bits of feather, which apparently fell from his winter coat when it was torn by barbed wire. Reporters who went to his home found it empty, with a neatly folded blanket put outside for the garbage collector to pick up.