China has shut down over 700 pornographic Web sites as part of a nationwide campaign, the state media reported on Wednesday.

Citing figures from the Ministry of Public Security, the report said 224 suspects have been detained since July 16, when the crackdown began.

Since the ministry publicised two telephone numbers and a Web site for people to report porn sites, it has received 733 calls and 16,711 online tips.

Photos, videos and articles attracting Internet users to join "pornographic activities online or organising sex trade" were targeted, the report said.

Wu Mingshan, an official in charge of the campaign, said "a clean online environment" has been established in major cities like Beijing and Shanghai.

Other future targets include online criminal activities like fraud and gambling, the official said.