YINCHUAN - Six suspects have been detained for producing counterfeit money, in northwest China's Ningxia Hui autonomous region, local police said Wednesday.

Police in Yinchuan, capital of Ningxia, received a report in August that a group were producing counterfeit banknotes and selling them online. The fake money was sold to more than 20 provinces and municipalities across the country.

After a three-month investigation, police captured the six suspects in Sichuan, Hunan and Henan provinces, confiscating counterfeit money with a face value of 200,000 yuan (30,287 US dollars). Printers, computers and moulds were also seized.

Further investigation showed the suspects had made counterfeit money worth over 3 million yuan, sending it out in more than 500 parcels.

Police are retrieving the circulated fake money, and an investigation is ongoing.