Chinese authorities have shut down dozens of Web sites that carried pornographic material or offered pirated movies or online games, the government announced Thursday.

Among those detained were two people accused of making $125,000 by running a pirated version of a game made by Chinese online game giant Shanda Interactive Entertainment, the official Xinhua News Agency reported.

Another site was fined $12,000 for letting customers download thousands of pirated movies, Xinhua said, citing an announcement by the government's anti-porn and anti-piracy task force.

Authorities closed 53 Web sites with pornographic or violent content, Xinhua said, without giving details.

"China is determined to protect copyright and will continue its efforts to fight against porn and piracy," Xinhua said.

China has the world's second-largest population of Internet users, with more than 100 million people online.

The government encourages Internet use for education and business but strictly controls content and tries to block access to material deemed pornographic or subversive.

Under pressure from China's trading partners, authorities have expanded their online enforcement in recent years to include illegally reproduced movies, music and software.