Story highlights Missionary couple helped to hide young North Korean defectors in China

The starving youngsters had crossed from North Korea looking for scraps of food

Eventually transported into Laos secretly in the hope of escaping to freedom

But they were caught and eventually sent back to North Korea and an uncertain future

"Pack your bags you're going to South Korea." These are the words nine young North Korean defectors had waited years to hear having traveled thousands of miles.

Unfortunately it was a lie.

The tragic story of this group of youngsters aged between 15 and 23 takes us back a few years when one by one they managed to cross the heavily-guarded border from North Korea into China to search for food. Most of them were orphans, while others had a parent unable or unwilling to look after them.

A South Korean missionary living in China, known only as M.J. to protect his identity, tried to help the youngsters and has broken his silence to CNN.

"This one child used to live with his father," he explained. "One day his father went into a North Korean military base trying to find food but was caught and beaten to death on the spot. The child witnessed this ... his mother then told him not to come home and threw rocks at him to keep him away."

Rodents 'a luxury'

The youngsters survived by foraging for scraps in trashcans. Fish bones and discarded rice were mixed to make a porridge, while rodents were considered a luxury. When M.J. first met some of them in December 2009, they had frostbite on their hands and toes from living in an old abandoned building where temperatures plummeted to as low as minus 30 degrees Celsius. Some of them had injuries from beatings by security guards and merchants when they were caught stealing food.

Photos: Images: Thwarted on brink of escape Photos: Images: Thwarted on brink of escape Defectors thwarted on the brink of escape – Young North Korean defectors pose for a photo with the South Korean missionary, known only as M.J. , a few days before they departed for the China-Laos border in May. M.J.'s face is obscured for his own safety. Hide Caption 1 of 6 Photos: Images: Thwarted on brink of escape Defectors thwarted on the brink of escape – The abandoned youngsters, aged between 15 and 23, had crossed into China to try to find food and shelter. They were sheltered by M.J. for two years. Hide Caption 2 of 6 Photos: Images: Thwarted on brink of escape Defectors thwarted on the brink of escape – From feeding out of dustbins and frequent beatings, to the joy of an amusement park trip in China, the group was given hope of a better life. Hide Caption 3 of 6 Photos: Images: Thwarted on brink of escape Defectors thwarted on the brink of escape – But their world came crashing down shortly after they crossed into Laos illegally on May 10, when they were caught by police without papers. Here they sleep at the detention center they were taken to. Hide Caption 4 of 6 Photos: Images: Thwarted on brink of escape Defectors thwarted on the brink of escape – They were kept in cramped conditions at the detention center for more than two weeks as they awaited their fate. Hide Caption 5 of 6 Photos: Images: Thwarted on brink of escape Defectors thwarted on the brink of escape – On May 27, the youngsters -- pictured at the detention center in Laos -- were sent back to North Korea and subsequently paraded as propaganda tools -- their future uncertain. Hide Caption 6 of 6

JUST WATCHED North Korean defectors face repatriation Replay More Videos ... MUST WATCH North Korean defectors face repatriation 02:19

JUST WATCHED North Korea defectors speak at UN inquiry Replay More Videos ... MUST WATCH North Korea defectors speak at UN inquiry 01:51

JUST WATCHED UN hears story of North Korean torture Replay More Videos ... MUST WATCH UN hears story of North Korean torture 01:24

JUST WATCHED Koreans push for family reunions Replay More Videos ... MUST WATCH Koreans push for family reunions 02:00

One of the nine, a 20-year-old man, told M.J. he wanted to live in China as "even beggars in China do not go hungry."

"These kids were suffering from malnutrition and disease," recalled M.J. "They had been living in quarters with bad sanitation ... also they all seemed to have suffered in one form or another from tuberculosis. Because they were suffering from malnutrition, their growth was stunted."

M.J. and his wife offered to help the youngsters leave China for Laos -- a landlocked country in South-East Asia -- and then onto a third country, perhaps South Korea or the United States to claim asylum. It is a route that is well traveled by defectors, and the missionary couple had already helped other North Koreans escape to a better life that way.

Living in fear

The nine lived with the couple and several other North Korean defectors in China for almost two years in constant fear of being discovered by the authorities. They could never leave the house during this time. China doesn't treat North Koreans in its territory as refugees and usually sends them back across the border.

"The children had been fugitives for a long time so they were used to this situation," he said. "We had a bed which was buttressed with quite a few books on the bottom as legs. The kids would go under the bed and kick out the books, so the bed would sit low and it would not look like anyone was hiding under it."

The couple tried to organize adoptive parents for the youngsters in the United States but without success. And so the long trip to the Laos border began.

The youngsters experienced some firsts along the way: One defector celebrated his birthday for the very first time; they visited an amusement park, which was a new experience; and they played barefoot on a beach for the first time. Finally, they were able to enjoy simple pleasures many children across the world take for granted.

"As we lived with these children, I saw them change," M.J.'s wife, who also asked not to be identified, said. "They started having hopes, they started dreaming and I know they were happier. I was overjoyed to have done something worthwhile."

The escape

After successfully getting six other defectors out of the country to safety via other routes, the missionary couple paid a broker to transport the remaining nine across the China-Laos border because they had no papers or passports. On about May 10 this year, they embarked on a journey that would take them through the jungle in the dead of night to avoid detection. This journey would ordinarily take 40 minutes, according to the missionaries, but this time it took four hours due to heavier than usual border security that day.

But crossing the border proved to be the easy part. On a bus en route to the capital, an unexpected police search changed the course of events. The youngsters were detained and then investigated for more than two weeks by Laotian immigration officials because of their lack of paperwork. M.J. admitted the police search surprised him as it had never happened with previous refugees he had helped pass through the country.

M.J.'s wife said they repeatedly called the South Korean Embassy in Laos for help. "We pled our case with the embassy because this was not just about one life but nine lives of young people ... for the embassy it was extra work and a burden to them and why should they care about these children from North Korea?"

M.J. said embassy officials told them to wait and do nothing to jeopardize things as Laos authorities were working to process the youngsters. He said no-one from the embassy visited them in eighteen days.

Bitter truth

On May 27, the Laos authorities told the youngsters to pack as they were being sent to South Korea. M.J. said they were so happy they all shouted for joy. Years in hiding seemed to finally be over. But the bitter truth of the situation soon became clear.

The missionary couple was prevented from following the children and instead locked in a room at the immigration offices for two hours. The United Nations' refugee agency, UNHCR, said the group had been sent back to North Korea via China.

Human rights groups were shocked. The missionaries were devastated.

"In these children's minds, they were going to South Korea," said M.J.'s wife. "They never imagined after crossing the border to Laos they would be sent back to North Korea."

The children have since been used for propaganda purposes in Pyongyang, appearing on state-run television in June claiming they had been tricked into leaving North Korea and expressing thanks to leader Kim Jong Un for saving them and bringing them back.

"What I am concerned about is what is going to happen after the propaganda is gone and the rhetoric is over," said M.J. "If we don't pay attention, if we don't keep asking where these children are, then these children will be lost forever and we will never know what happened to them."

Laos was widely criticized for its actions by the U.N. and human rights groups but insists the youngsters were in their country illegally and that the missionaries were effectively human traffickers.

South Korea's foreign ministry told CNN it prioritizes the life and safety of North Korean defectors and is "inspecting the problems revealed from this incident and has improved and strengthened the overall support system."

But M.J. and his wife fear for the nine youngsters, who dreamed of a life without hunger and fear.