THREE helpless young North Korean escapees stare out from their cell, caught in the middle of a tug of war to decide whether they will be set free or sent home to face deprivation, punishment and the risk of death.

Their photograph and letters smuggled out of prison represent a desperate appeal this weekend to the international community and the United Nations to persuade the government of Laos to reject demands from the North Korean embassy to hand over the children.

The trio - an orphaned brother and sister aged 12 and 13, and a sick girl of 16 - are imprisoned in a crumbling jail in Vientiane, the Lao capital, only a few hundred yards from the Mekong river that divides Laos from Thailand.

“I can hardly sleep for fear,” said Choi Hyang, the 13-year-old girl, in a handwritten note in Korean shown to The Sunday Times. “If you don’t help they’re going to kill us,” her brother, Choi Hyok, wrote. “If we’re sent back we will face certain death,” added Choi Hyang-mi, their teenage companion.

There are well documented accounts of grotesque abuses inflicted on refugees deported to North Korea. A few have been beaten to death on their arrival at frontier posts. Prisoners can be yoked together like animals, their hands or collarbones pierced with barbed wire. Pregnant women face forced abortions. Some women have said that newborn babies are killed.

The three children were caught by Lao paramilitary police on November 19 last year, just as they reached the final leg of a 1,700-mile odyssey from the frozen borderlands of northeast China to the jungles of southeast Asia.

The trail has been followed by hundreds of North Koreans fleeing hunger and repression to seek asylum in Thailand, where they can be processed by the UN refugee agency UNHCR and accepted by foreign embassies.

But in their short lives, these three have been unluckier than most and bad fortune has dogged every step.

Choi Hyok and his sister lost their parents in the 1990s, when more than 1m died of famine under Kim Jong-il’s dictatorship. They were reduced to begging in the streets of Hoeryong in one of the poorest parts of North Korea, on the border with China.

“I was always very hungry, cold, worked hard and was beaten all over my body when I was a beggar,” the boy recalled. “All our relatives were too poor to help us,” his sister said, “so we escaped to China in 2005.”

There they met Choi Hyang-mi, whose father had died in the 1990s and who fled to China across the Tumen river in December, 2003. She appears to suffer from a congenital heart complaint, made worse by malnutrition and stress.

The children came together in the care of a group of Christian missionaries near the city of Shenyang. The account of their journey, together with the photos and letters, were provided by refugee activists to The Sunday Times on condition that precise details were not disclosed.

After months of preparation, they boarded a train to Beijing, with just enough money to get by and two precious phone numbers for Korean Christians in the United States. They evaded document checks in the Chinese capital and caught another train for the long haul down to Kunming, in China’s southwest.

From there they went by bus and taxi to where China blends into Laos under a canopy of tropical jungle. They walked for 10 hours over seven hilltops to reach the first Lao settlement.

Then they rode on rickety buses down trails popular with gap-year backpackers, past the towns of Luang Prabang and Vang Vieng, to the Lao capital on the banks of the Mekong. Sanctuary in Thailand lay in sight across the muddy waters.

But the children had no way of knowing their arrival coincided with a state visit by Hu Jintao, the Chinese leader, to the authoritar-ian communist regime that runs Laos. They were picked up within hours. Their only stroke of luck came when a kindly officer lent them a mobile phone. The children called the United States to plead for rescue.

At first, Christian activists allege, Lao police officers sought a ransom of £500 a child. When the bargaining got nasty, the three were brought before a court, fined and jailed for three months for entering the country illegally.

Their bad luck then turned into terrible misfortune when the Lao authorities allowed three heavyweight “counsellors” from the North Korean embassy to visit them. It was, by the children’s accounts, a terrifying experience. The diplomats shouted and swore at them. They talked about “the party’s generous forgiveness” one moment and threatened violent retribution for “traitors” the next.

Afterwards, Choi Hyok went from being a confident youth, so sharp that he had picked up the complex Lao language in jail and conversed in it with his captors, to a trembling, frightened boy crying for his mother.

He clung to his sister, who developed constant stomach pains and could not shake off the flu. “Any sudden noise now startles me,” she wrote. To add to the fear of the older girl, Choi Hyang-mi, the strain accentuated her angina pains. The next time a Christian activist was allowed to see the trio, he was horrified.

“They were cast down and gloomy. Before, they always asked for pork and beef but they lost their appetites,” he said. His group went public with the children’s plight.

The South Korean ambassador in Vientiane is now negotiating with the authorities. The Lao foreign ministry says there will be no demands for ransom. The North Korean embassy did not answer phone calls and a guard slammed its gates on inquirers.

Last Thursday night, 13 lucky North Korean refugees slipped down to the banks of the Mekong, boarded a speedboat and crossed to Thailand, reaching safety in Bangkok some 20 hours later.

The unlucky three remain in their hot, fetid jail, clinging to their dreams - Choi Hyok and his sister want to be doctors, while Choi Hyang-mi just yearns to find her family. The negotiations continue tomorrow.

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