Police in southern China have arrested 16 people allegedly involved in kidnapping and selling baby girls as young as newborns to foreigners, state news reports said.

Thirty-one babies ranging in age from a few days to several months were kidnapped from the southern province of Guangdong and sold via middle men to two welfare organizations in neighboring Hunan province, the official Xinhua News Agency said in an article posted on its Web site Friday.

The babies were sold for between $100 and $500 each, the report said.

Xinhua said the ring, which had allegedly been in operation for two years, sold some of the girls to foreigners. An investigation was underway to track down where the babies came from and where they are now, it said. The report did not give the names of the welfare organizations.

Police arrested two of the suspected traffickers at a Hunan railway station last month as they were delivering three infants, Xinhua said. The arrests led police to 14 other suspects, including seven officials with welfare groups in Hunan province, it said, citing Xiao Haibo, deputy director with the Hengyang Public Security Bureau.

China has an active black market in babies and young women, who are bought or abducted and sold to couples who want another child, a future bride for a son or a household servant.

In August, a court in the southern province of Fujian sentenced two men to death for heading gangs that bought 82 children from their parents and sold them to families in Singapore.