SEOUL, South Korea — North Korea's prison population has swelled in recent years with those caught fleeing the country under a crackdown on defections by young leader Kim Jong Un, according to defectors living in South Korea and researchers who study Pyongyang's notorious network of labor camps and detention centers.
Soon after he succeeded his father as North Korean leader, Kim is believed to have tightened security on the country's borders and pressured Pyongyang's neighbor and main ally, China, to repatriate anyone caught on its side of the frontier.
In interviews with The Associated Press and accounts collected by human rights groups, North Koreans who have managed to leave the country say those who are caught are sent to brutal facilities where they now number in the thousands.
"They are tightening the noose," said Insung Kim, a researcher from the Database Center for North Korean Human Rights who gets to interview most defectors soon after their arrival in South Korea. "This is to set an example to the North Korean people."
The plight of those caught fleeing the North was highlighted last month when nine young North Koreans were detained in Laos, a key stop along a clandestine escape route through Southeast Asia that had previously been thought safe. Instead, the Lao government turned them over to Pyongyang.
While the high-profile nature of their repatriation might offer them some protection, human rights group fear for them.
"Forced repatriation from China is a pathway to pain, suffering, and violence," according to "Hidden Gulags," an exhaustive 2012 study on the prison camp system based on detailed interviews with defectors. "Arbitrary detention, torture and forced labor are inflicted upon many repatriated North Koreans."
In 2003, Park Seong-hyeok, then 7, and his parents were arrested trying to reach Mongolia from China and sent back to North Korea. He ended up at a prison in the northern city of Chongjin, where he was packed in with other kids, some of them homeless children rounded up off the streets.
They were blindfolded each day and forced to clear land for agriculture, he said. If they refused, they were beaten.
"I couldn't even tell whether I was alive," Park said. "We were provided five pieces of potato a day, each about the size of a fingernail. "
After a few months, he managed to escape after his uncle bribed the guards. With the help of relatives, he made it to South Korea, where he now attends a special school for North Korean defectors. But he assumes his parents, who he has not seen in 10 years, remain imprisoned in the North.
In the 18 months since Kim took power, any hopes the 20-something ruler would usher in a new era of human rights reforms have been squelched. Instead he has overseen a campaign to lock down the borders and pressure the North's neighbor and main ally, China, to repatriate defectors.
Defectors pose a particular threat to the Pyongyang regime, human rights groups say, because of the stories they tell the world about the plight of the North Korean people, and the information and money they send back in.
North Korea considers those who leave the country to be guilty of treason and subject to up to five years of manual labor.
In addition, the penal code states if the nature of the defection is "serious" — taken by most researchers to mean if the defector gets the help of South Korean or American Christian missionary groups as opposed to trying to reach China for work purposes — the defector risks an additional charge of anti-state activities that could mean life in prison or even death.
North Koreans considered hostile to the government can spend the rest of their life, along with their families, in one of at least five sprawling labor camps or colonies that encompass fields, factories, mines and housing blocks.
Modeled on the Soviet Gulag system, the areas are chosen for their natural barriers, such as mountains and rivers, their remoteness, and their access to natural resources like wood and coal, according to human rights groups.
Defectors may end up in those camps, but are typically held first in other detention facilities close to the border, just as brutal but more resembling traditional penitentiaries, according to human rights groups. Still, at least one labor camp, Yodok, now has a special section for those repatriated from China that houses thousands of inmates, according to Kang Cheol-hwan, a former inmate there.
Kang, who recounted his experiences at the camp in the book "The Aquariums of Pyongyang," said his information came from contacts in the North. He currently heads a foreign-funded campaigning and advocacy group aimed at spreading democracy in North Korea.
Estimates of the current prison population range from 100,000 to 200,000.
One human rights activist said based on his interviews, would-be defectors now account for about 5 percent of the total inmate population. He didn't give his name because the estimate was based on his own research and is not the official data of his organization.
Insung Kim of the Database Center for North Korean Human Rights cites a "five-fold rise" in the number of detained defectors over the last 10 years.
"When people get caught, a car comes to their house in the middle of the night and takes them away," said a recent defector, a 17-year-old who asked his name not to be used out of fear relatives in the North might be targeted. "And they don't come back."
The boy, also a student at the defector school in South Korea, worked as a street lookout for his father, who organized the smuggling of money and people across the Chinese border. He fled with his family in 2012 after word got out about the nature of the family business.
"The monitoring has got more intense, there are more patrols," he said of security along the border.
Figures provided by the South Korean government appear to support numerous accounts by smugglers, defectors and people living along the border that security has been tightened. In 2009, 2,929 defectors made it to South Korea. Last year, 1,509 did, the lowest number since 2005.
The government said there had been no sign of positive change in human rights inside North Korea since Kim Jong Un came to power. "From defector accounts, it appears prison camps are still being operated, and control on society, including the flow of information, is toughening," it said in a statement.
Despite ever more detailed and consistent testimony by defectors and sharper satellite images of the prison camps, there is still little the international community can do to press for change inside a country that has consistently shown no willingness to engage on human rights issues.
The government refuses to allow outsiders access to detention facilities to check conditions, and denies the existence of political prison camps altogether.
The United States' main focus is on getting Pyongyang to resume international talks about giving up its nuclear weapons program. Most other governments believe increased contact with the regime and its people— not sanctions or threats — is the best way to improve conditions.
The United Nations will in July begin a high-level commission of inquiry into human rights in North Korea, but few expect Pyongyang will allow U.N. researchers access to the country, let alone the camps.
"The U.S. government can't do much of anything," said David Hawk, a veteran human rights researcher and author of the "Hidden Gulag" report. "If North Korea wants to maintain its self-imposed isolation, there is very little that the outside world can do except record the grotesqueness of the violations and condemn them."
The main source of information about the prison camps and the conditions inside is the nearly 25,000 defectors living in South Korea, the majority of whom have arrived over the last five years. Researchers admit their picture is incomplete at best, and there is reason for some caution when assessing defector accounts.
Only a tiny percentage of the defectors were themselves imprisoned or worked as guards in the camps. On their arrival in the country, all spend three months at a center run by South Korea's intelligence agency, where they are pumped for information, in part to establish whether they might be spies. It often takes several years for defectors to reach South Korea, so their information is rarely current. Some ask for money to be interviewed.
Jung Gwang-il, who fled the North in 2004 after spending three years at Yodok for alleged espionage, said prisoners were forced to grow corn, peppers and barley, and those who didn't work hard enough had their rations cut. Hunger was so intense that prisoners ate undigested seeds from the feces of other inmates, he said.
In April, they would collect the corpses of those who died over the winter, because they were unable to bury them in the frozen earth.
"To this day I still remember the smell," he said. "Death was a fact of life there."
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