Police in central China have launched an investigation into the disappearance of more than 100 Vietnamese women who married local bachelors and had been living in villages around the city of Handan.
The women all disappeared at the same time in late November, along with a Vietnamese woman who married a local villager 20 years ago and had introduced most of the brides to local men in recent months in exchange for a fee.
Faced with severe gender imbalances as a result of China's decades-old one-child policy and a traditional preference for male children, many Chinese men are unable to find suitable brides and resort to paying for wives from poorer Asian countries such as Vietnam.
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Particularly in more traditional rural parts of China, marriage is highly transactional and men are increasingly expected to provide a house, car, electrical appliances and a steady income before a woman or their family will consider him eligible for marriage.
For those who cannot afford the expensive requirements of Chinese brides, paying for a bride from Vietnam or elsewhere in the region can be a much cheaper option.
As a consequence of the demand for cheap foreign brides, China has an enormous problem with human trafficking.
"My brother worked outside the village and was too poor to afford a local wife so my family paid Rmb100,000 to get a wife from Vietnam through that old Vietnamese woman who came here 20 years ago," said the brother of Bai Baoxing, a local man whose Vietnamese wife disappeared with the others barely a month after they were married. Mr Bai's brother said the new bride spoke decent Mandarin Chinese and he and his family were now wondering whether she was even Vietnamese.
Chinese media reports identified the absconded Vietnamese marriage broker as Wu Meiyu.
After living in a village on the outskirts of Handan for 20 years, she started offering introductions to Vietnamese brides for a fee at the start of this year.
An officer in the local Handan city police office told the Financial Times that provincial police were now handling the case and they could not comment on the ongoing investigation.
Chinese media are filled with cases of women from poor rural areas who are abducted and sold into marriage, as well as cases involving foreign brides.
Local officials in Handan said it was possible the Vietnamese brides had organised their mass departure through social media networks.
"Chinese law prohibits marriage brokers from selling Chinese brides abroad and it is also illegal for Chinese to buy brides from Vietnam," said Chen Shiqu, a celebrity policeman working in China's anti-human trafficking task force, in a comment posted online. "We should strike hard against human trafficking and marriage fraud."
At present, there are 118 males born for every 100 females in China and by 2020 there will be around 20m unmarried men in the country, according to government research.
Mass migration to the cities has exacerbated the problem for rural men as most eligible women born in rural areas prefer to marry wealthier, more sophisticated men from the cities.
In the villages around Handan city, men are said to be expected to provide "1.5kg and a vroom" — slang for Rmb100,000 ($16,000) in Rmb100 notes (weighing about 1.5kg) and a car — for their new bride.
With the added expectation of a house in the village and a full suite of electrical appliances, local bachelors estimate the total cost of attracting a wife is about Rmb400,000, compared with the roughly Rmb100,000 Ms Wu allegedly charged for a Vietnamese bride.