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 middlemen to two welfare organizations in neighboring Hunan province, the official New China News Agency reported on its Web site Friday.

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

The report also said the ring, alleged to have 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 provide the names of the welfare organizations.

Police arrested two of the suspected traffickers at a Hunan railway station last month as they were dropping off three infants, the news agency 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 of 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.