Fengxian district police have arrested 11 people suspected of illegally selling personal information, local media reported Wednesday.

The case involved about 1 billion pieces of personal information, according to a report in the Shanghai Evening Post.

Fengxian district police got onto the case in June while they were investigating an illegal gold dealer, according to the report. The dealer told police that he bought his clients' personal information online from a contact on QQ, an instant messaging service. Investigators traced the seller's QQ number and bank account information to a resident living in Liupanshui, Guizhou Province.

Police went to Liupanshui in mid-October to raid the ring, which had been selling personal information since April. Police found 1 billion pieces of information, including those of property owners in high-end residential compounds in Shanghai.

According to the report, the ring had made more than 2 million yuan ($320,878) selling the information.

It is unclear how the 11-person ring obtained the information or whom they sold it to. Police said the case remains under investigation.

"Many suspects buy personal information to find customers for their businesses," said Li Xiaohua, a lawyer with the Shanghai Lixiaohua Law Firm. "It can cause residents a lot of trouble. Some even get scammed out of money after losing their personal information."