Popular websites, including news portal Sina, search engine Baidu and social networking Tianya, have been ordered to make changes after being found to have carried pornographic content, according to the National Office against Pornographic and Illegal Publications.

The office found Sina's blogging and file-sharing sites carried "obscene" fiction such as "Lascivious story of a tutor" and "Queen and Lolita," Baidu had stories such as "Mansion of desire," and Tianya had stories such as "Ten women."

Authorities in Beijing have talked with the management of Sina and Baidu, ordering them to delete the vulgar content and clean up their blogging, file-sharing and social networking services. More than 145,000 posts containing vulgar information have been removed, and 103 user accounts were shut down.

The two websites were fined 30,000 yuan ($4,900) each.

Authorities in Hainan Province fined Tianya 10,000 yuan. The website cleaned up 75 pornographic or vulgar articles in blogs or posts, and suspended 17 accounts. The website has also assigned people to monitor information on its front page or in their special topic pages.

The national anti-pornography office said the monitoring of Internet porn will continue, and problems will be immediately and seriously dealt with.

The portal websites, which have a large social influence, should discipline themselves more strictly than others, the office said.