A HONG KONG man was reunited with his 9-year-old son Friday morning in Shenzhen three days after the boy was allegedly kidnapped by his mainland girlfriend.

Yao, a 52-year-old Hong Kong carpenter, lives with his Guizhou girlfriend surnamed Chen and his son by his ex-wife in Huanggang Village, Chinese media said.

Chen took the mentally handicapped boy, Long Long, on a trip back to her hometown Aug. 23, but suddenly called Yao Tuesday demanding 250,000 yuan (US$32,900), saying the boy had been kidnapped.

Yao, who has been married twice before, has two adult sons from his first marriage in the SAR. Yao's second wife, a Guangxi woman 17 years his junior, gave birth to Long Long in 1999 but was not able to get a Hong Kong residency permit. The couple split in 2002 but remain married.

"I met my present girlfriend Chen in a karaoke bar two years ago. She was 28, jobless, and only has a primary school education," Yao said.

They rent an apartment together in Huanggang, and Yao said he gives her almost half of his monthly 15,000-yuan salary. "I live with her mainly because I hoped she would take care of Long Long," he said.

Yao had wanted to marry Chen, but as he has not been legally divorced has not been able to. Long Long stays with him in Hong Kong Monday to Friday, where the boy goes to school and spend weekends together with Chen in Shenzhen.

"We were peaceful and happy. I don't give Chen much money, and she doesn't ask. Then in August, she told me her home had suffered flooding and I gave her an extra 5,000 yuan."

Chen said she wanted to visit her home in Guizhou and took Long Long with her on the trip.

"She called me Tuesday morning, saying my son was missing and kidnappers had asked for 250,000 yuan. She also gave me details of a bank account," Yao said.

Yao panicked because he did not have such a big sum. Chen called the second day, lowering the ransom to 150,000 yuan.

"She also asked me how much I had. When I said 40,000 yuan, she replied if that's all, 40,000 yuan would do."

Then Yao suspected it was Chen who had demanded the money, and called Shenzhen and Hong Kong police.

The breakthrough came as Yao was about to board a train to Guizhou and help local police investigate the case. Chen told him in a phone call Thursday that she had put Long Long onto a train bound for Shenzhen and asked him to meet the boy at the railway station.

"Long Long has mental problems. He is 9, but has the intelligence of a 5-year-old. It would take a whole 24 hours for the train to arrive. If he went missing again at some small village station, I could lose him completely. Besides, he would need to eat," Yao said.

He asked for help from Shenzhen railway police, who immediately contacted colleagues to search for the boy on Shenzhen-bound trains.

"We didn't dare take a chance. A mentally challenged Hong Kong boy named Yu Wenhan went missing several years ago. He is still missing today," said Wang Jun, a local police officer.

Transport police found the boy on the train and reunited him with his father at the Shenzhen west railway station. "I was not kidnapped. A sister took me to herd the cows in Guizhou," the boy told police.

"Chen had helped me take care of the boy, cook and do the laundry. I've no idea why she did this. I had hoped to live here and marry a mainland woman after retirement. But it seems unrealistic now," Yao said.

Gao Haiyan, a researcher with the Shenzhen Academy of Social Sciences, said cross-border families, like Yao's case, are unstable.

"The husband can travel between Hong Kong and Shenzhen, while the wife often has a lonely life in Shenzhen. The woman tends to feel hard done by and insecure after some time," she said.

Gao has called on the Hong Kong government to consider the issue and draw up policies to help unite cross-border families.

(Li Dan)