FOREIGNERS have long been attracted to Sapa and its surrounding mountains in the far north of Vietnam. First it was the French colonists, who built a hill station there. More recently it has been tourists, who come to enjoy the stunning landscape of terraced rice paddies and the colourful world of the Hmong tribes, with their distinctive red, black or “flower” dress. But now, it seems, another type of visitor is finding this territory attractive: gangs of kidnappers who snatch young Hmong women for sale as brides across the border in China.

The kidnapping has been going on for some time, and locals talk of a number of cases so far this year. The abductions follow a pattern: a Hmong girl is wooed by an out-of-towner—whether from Vietnam or China is not clear—who speaks her language. She is lured to a rendezvous to be drugged and smuggled into China, probably near Lao Cai, about an hour's drive from Sapa. Tall, pretty girls are said to be particular targets.

One 18-year-old recently managed to get back home to tell her tale after a four-day ordeal. Held captive in China, she escaped through a window and contacted the Chinese police, who returned her to Vietnam. Most do not escape. One of those kidnapped last month was a married woman with a son; friends fear her family may never see her again.

There is some tradition of bride-kidnapping among the Hmong themselves, but this gangsterised, cross-border variety is especially cruel. Village girls with little knowledge of the outside world tend to be trusting. And the kidnappers seem to operate with impunity—even, according to one account, seeking a reward for returning two underage girls whom they had failed to sell in China.

Within China itself, the abduction and sale of women has long been recognised as a prevalent social evil. Three decades of strict family-planning policies have exacerbated a traditional preference for boy children and contributed to a shortage of marriageable women.

Relations between Vietnam and China along their 1,300km (800-mile) border have improved: last month officials from the two countries, which fought a brief but bloody border war in 1979, completed a seven-year effort to demarcate the frontier. This, they hope, will open the way for increased links of various sorts. Stepped-up police co-operation to stamp out an evil little trade in Hmong women would be a good start.