The crackdown appeared aimed at eradicating porn more than copyright infringement, though pirated DVDs, software and books are sold at many stalls and street corners around China. It follows a government campaign against online pornography launched in January that has seen dozens of arrests and over 2,000 Web sites closed.

Thirteen people from two of the pirating rings have been sentenced this year on charges of copyright violations or selling obscene materials, according to a statement on the Web site of China's General Administration of Press and Publication (GAPP).