Communist authorities have arrested the family of North Koreans who provided the world with the first documentary evidence that their country is using live political prisoners to test its growing arsenal of chemical and biological weapons.
Kim Sang Hun, a 70-year-old retired UN official and South Korean human rights activist, who planned the family's escape, said three family members were seized a month ago as they attempted to leave via China and reach South Korea via Thailand.
And last week North Korean agents attempted to abduct the eldest son, the only member of the family still at large, as he was waiting to greet them in Bangkok. He had escaped to South Korea five years ago. "He was walking on the street when two North Koreans jumped out of a Mercedes and tried to grab him but he fought them off and ran away," Mr Kim said. "They will do anything to get these documents back."
The family's fate can now only be guessed at and Mr Kim blames himself for not having got the family out sooner. For three agonising months he haggled over the price of getting the family out and tried to raise money from charity groups to finance the smuggling operation. Many of the cloak-and-dagger negotiations took place over a Chinese mobile phone network that now extends into border areas of North Korea, making it possible, although risky, to contact people directly from Seoul.
Mr Kim largely relies on his own savings to help North Koreans escape and to bribe officials to provide documentary evidence of the terrible stories the refugees are taking with them. There are now at least 4,000 refugees in the South, possibly far more, and among them are those with eyewitness accounts of the horrors of Kim Jong Il's regime.
"For years we heard these stories that live prisoners were being used but there was no evidence," Mr Kim said. Then he came across one refugee whose father worked as a janitor at the "February 8" Vinalon factory in Hamhung, on the east coast of North Korea. The factory was the brainchild of North Korea's most famous scientist, Lee Sung Ki who introduced a technology to produce a chemical fibre made from calcium carbide called Vinalon. The Japanese-trained scientist became a favourite of the late Kim Il Sung, who put him in charge of the country's extensive chemical and biological weapons programmes and used the country's Vinalon and fertiliser plants for dual purposes.
South Korea believes the North has at least 5,000 tons of materials for nerve gases such as VX and sarin, blood agents, and the mustard-gas family of chemical weapons. It has large stockpiles of shells filled with poison gas. Recently the US Assistant Secretary of State, John Bolton, called it "one of the most robust offensive bio-weapons programmes on earth".
One defector, Kim Dae Ho, who spent 10 years working on the North's nuclear programme, said: "I know that they used to test the weapons on dogs at the National Defence College in Kangye. Colleagues told me they used prisoners as guinea pigs but there was no proof."
Only a handful of people have ever emerged alive from North Korea's gulag to bear witness. One of the first detailed accounts has came from Soon Ok-Lee, who served at a woman's prison camp where, in 1988, she saw 50 fellow inmates die after being fed cabbage laced with chemicals as scientists in white surgical gowns watched. Two years later, she witnessed 150 prisoners dying in chemical fumes on a hillside, observed by guards in gas masks. She also heard those supervising the experiment praising the name of the scientist Lee Sung Ki.
Many prisoners, especially young and healthy men, were also transferred out of the camps to work on special military projects and it is thought that they were used to build secret tunnels and then buried alive. Others are alleged by one former prison guard to have been operated on, often without anaesthetics, by trainee surgeons.
At the Hamhung Vinalon plant, the head of the arrested family, a 57-year-old engineer whose spine had been broken when he was falsely accused of treason, agreed to help with the search for proof. He had heard that another plant, called "Daily Site No 2" four miles away at Hungnam city, had a strange reputation.
"It was a chemical factory. It was difficult even to breathe because of the unpleasant chemical smell all around," he told Mr Kim. "While I was inspecting the power unit, I saw a prisoner truck that looked like a freezer truck arriving. I noticed a strange expression on the face of the officer. The steel gate of a tunnel opened automatically and the truck disappeared inside."
Once inside the tunnel he got a brief glimpse of what was going on. "There were boxes that looked like aluminium about the size of a large freezer. Each box had a door in front with a large round window. I witnessed with my own eyes human hands moving inside two of the boxes. I was breathless with shock."
He found out that the State Security Agency delivered truckloads of prisoners twice a month. Later he went into the plant manager's office and saw records lying on a desk. He grabbed four transfer authorisations from a thick pile of similar orders lying on a desk, crumpled them up and threw them in waste paper basket so he could retrieve them later on in safety.
Each document gives sparse biographical details of an individual and authorises his or her transfer from a prison specifically for the purpose of "human experimentation of liquid gas for chemical weapons testing in live experiments". Forms are dated as late as July 2002.
Mr Kim thinks the North Korean secret police launched the search for the engineer, his wife and second son after the documents were found to be missing. He now also fears that they may have sacrificed their lives in vain.
Seoul is doing its best to ignore anything that might harm its efforts to foster good relations with Pyongyang and to encourage North Korea to take part in the six-nation talks that resume in Beijing this month. It has dismissed the documents and the testimony of another defector, Kwon Hyuk, who described in a recent BBC documentary how he saw whole families being gassed, as unreliable.Reuse content