An increasing number of women from Southeast Asia are being smuggled into China and sold into marriage or forced to work as prostitutes, according to a state media report.

"The number of foreign women trafficked to China is definitely rising," the report in the China Daily quoted Chen Shiqu, director of the office for combating human trafficking in the Ministry of Public Security, as saying.

Without giving figures, he said that many trafficked women come from poor rural areas of Vietnam, Myanmar or Laos and are lured by transnational criminal gangs with promises of good jobs or marriage with rich Chinese men.

On arriving in China, the victims are often sold to villagers as brides or forced to become sex workers in underground brothels in coastal or border areas such as Guangdong and Yunnan provinces, he said.

Women are sold for between 20,000 yuan ($3,100) and 50,000 yuan each, with prices varying with appearance and nationality, Jin Yulu, an official at the Ruili border crossing to Myanmar, told the China Daily.

Some Southeast Asian women are transported as far as Hebei province in the north, which surrounds Beijing, where police have rescued 206 women since April 2009, the report quoted the provincial public security department as saying.

Sex selection combined with China's population control rules has led to a gender imbalance in the country, with 118.1 boys currently born for every 100 girls against a natural ratio of 105 boys for every 100 girls, according to UN figures.