Thirty-five years after she vanished from Macau, relatives of a Thai woman believed to have been snatched by North Korean agents hope that a landmark UN investigation will help to finally bring her home.

Anocha Panjoy was 23 when she left her apartment in May 1978 in the former Portuguese colony, where she was working at the time, telling a friend she was going to a beauty parlor. She never returned.

Her disappearance was a mystery for almost three decades until former US army deserter Charles Jenkins revealed that a Thai woman called Anocha had been his neighbour in Pyongyang.

"When Anocha disappeared, I thought that she was killed in Macau and her body was dumped in the sea," her nephew Bangjong Panjoy said.

"The day we heard she was in North Korea, the whole family cried as they thought Anocha would come home. We cried and cried wanting her to come back," he told AFP.

Anocha's father died just months before her whereabouts was revealed.

When Bangjong visited Japan to meet Jenkins, the American's Japanese wife Hitomi Soga -- another former abductee -- immediately recognised Anocha in the family's photos, he said.

According to Jenkins, who spent four decades in North Korea until he was allowed to leave in 2004, Anocha told him she was forced into a boat and taken against her will to the secretive communist state.

Bangjong believes that Anocha was probably kidnapped by North Korea to be the wife of a foreign defector, or to teach the Thai language to North Korean spies.

The family recently submitted its evidence about her abduction to the UN Commission of Inquiry into Human Rights in North Korea, which was set up in March under the chairmanship of former Australian judge Michael Kirby.

The commission is the first UN expert panel to officially examine Pyongyang's human rights record, by collecting witness testimony in Japan, Thailand, Britain and the United States from North Korean defectors and other victims.

Pyongyang -- which has refused to cooperate with the commission -- has in the past admitted kidnapping Japanese nationals, mostly in the 1970s, to train its spies.

But according to Thai officials, North Korea has repeatedly denied abducting Anocha, who would be 59 years old if still alive today.

'Too poor to matter'

After an initial unsuccessful push by Thailand to secure her release, her relatives say they feel abandoned by their government.

"If Anocha was the child of privileged people in this country, she would have received help by now -- people would be enthusiastic to help," Bangjong said.

"Anocha is the child of poor people from the country so the authorities don't think it's important," he added.

International human rights campaigners are urging the Thai government to step up pressure on Pyongyang to reveal what happened to Anocha.

"Instead of making excuses it's time for the Thai government to stand up and tell North Korea that they have to come clean on this case," said Phil Robertson, deputy Asia director at New York-based Human Rights Watch.

The Thai foreign ministry denies it has given up trying to bring Anocha home.

"The ministry has constantly raised this case with North Korean officials who have repeatedly denied that Anocha is in North Korea," foreign ministry spokesman Manasvi Srisodapol said.

At the family home in Sankampaeng, which was paid for with the money Anocha sent home from her wages, her clothes and belongings are still in her room waiting for her.

"Anocha saved money and sent it to her father to build the house where we live today. Even if she doesn't come back, we will keep it as a memorial," Bangjong said.

After decades of waiting and hoping, Anocha's relatives hope that the UN probe will finally shed light on her disappearance.

Presenting some of its findings so far, judge Kirby last week spotlighted "unspeakable atrocities" in North Korea's political prison camps, citing survivors who saw babies drowned, had relatives killed before their eyes, and lived on vermin.

The final report is due to be submitted to the UN Human Rights Council in March next year, and Kirby has said he expects the UN to act on any recommendations it might make.

But with no known sightings of Anocha since Jenkins last saw her in 1989, her family are also prepared for the worst.

"Even if she cannot return alive, even if Anocha is dead, we wish at least to receive her bones wrapped in white cloth," Bangjong said.

"She can come home alive and walking or wrapped up. We still want to know that it's her, Anocha."