The house where a Vietnamese woman killed her Chinese husband and mother-in-law in South China's Guangdong province on March 2. [Photo/IC]

When Lai Shehui arrived at his home at Guangbei village in Raoping county in Chaozhou, South China's Guangdong province, on the early morning of March 2, he found his wife and son dead, with their hands and feet tied. His daughter-in-law from Vietnam and the two-month-old baby twins went missing.

Lai said that the 21-year-old Vietnamese woman called A You was "bought" for 28,000 yuan ($4,520) from a matchmaker last year to marry his 32-year-old son.

The matchmaker is a middle-aged Vietnamese woman who has acted as go-between for Vietnamese women and Chinese bachelors for years, said the 60-year-old.

"Because she is expected to carry on the family line, we did not ask her to work a lot," said Lai Shehui. But since she was pregnant last May, she has run away from home repeatedly before she was found later, he added.

Fifteen hours after the homicide was reported, the police found Lai's two grandsons and the Vietnamese "bride" in another town, where the woman intended to sell her twin babies.

According to the police, A You and three male Vietnamese accomplices strangled her husband and mother-in-law to death when they stopped them from making noise at her home.

The buyers and broker involved in the baby trafficking case have also been arrested.

Illegal cross-border marriage is nothing new in China, especially in some impoverished villages where bachelors find it difficulty to marry a native bride.

It is partly because of the gender imbalance as a result of the tradition, especially in rural areas, that boys are the only recognized heirs to carry on the family line, and partly because many young rural women move to cities through marriage amid rapid urbanization.

Local police said because the Vietnamese "brides" have no hukou, or household registration, and their marriage is illegal, they have difficulty in fitting in local life. As a result, many of them run away from their husbands not long after they are married and go on to sell themselves to other Chinese bachelors to profit from the marriage.

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