Two Taiwanese movie piracy rings used a hotline operated by the Motion Picture Association (MPA) to try to put each other out of business.

The calls resulted in Taiwanese police raiding two separate sites in the city of Taichung on Monday and seizing 117 DVD-R (recordable DVD) and CD-R (recordable CD) burners, capable of producing 1.7million DVD-Rs and 2.7 million CD-Rs in one year, the MPA said.

Investigators from the Foundation for the Protection of Film and Video Works (FVWP), which represents the MPA in Taiwan, were with police during both raids, and were surprised to see that one of the suspects from the first raid was a man who had provided them with information about the other ring just days earlier.

At the second police raid, a suspect admitted to using the MPA hotline to provide the tip used in the first raid, the FVWP said.

Last year, Taiwanese law-enforcement agencies seized 1,552 optical disc burners during raids.

Studios affiliated with the MPA, including Buena Vista International, Paramount Pictures and Sony Pictures, lost $6.1bn to global movie piracy in 2005, with $1.2bn of that from the Asia-Pacific and $1.3bn in the US, according to figures provided by the MPA.