SHIJIAZHUANG - Police in North China's Hebei province have rescued 206 foreign women who were illegally purchased by desperate bachelors over the last two years, local officials said Thursday.

Police in the province also rescued 3,500 women and children abducted from areas around China as part of a campaign against human trafficking, said Yan Zeli, an official from the provincial public security bureau.

Yan said some rural families in Hebei still retain an old custom of purchasing wives for men who cannot find suitable Chinese spouses. These families have been more able to afford to buy mail-order wives in recent years, as their incomes have increased.

Police have busted more than 429 trafficking rings and arrested 556 suspects since the campaign started in 2009, Yan said.

The mail-order bride trade is not isolated to Hebei. In the past, women were sometimes kidnapped from relatively poor areas in southwest China and sold to rural families in the wealthier central and eastern provinces. However, mail-order brides have become more popular in recent years.

"Some foreign women are tricked into moving to rural China for job opportunities or false marriages," Yan said, adding that the women come from a host of countries, including Laos, Vietnam, Thailand, Cambodia, the Democratic People's Republic of Korea (DPRK) and Mongolia.

Yan said police are helping the women return to their home countries.