"Sina.com, as a large-scale Internet portal with a quantity of Internet users including minors, should have abided by the law to seek profits, but it ignored the law and took the form of network literature and audiovisual programs to openly spread pornographic information resulting in great harm to the society," Zhou said.

"Internet information service enterprises should draw a lesson from Sina and give great importance to supervising their online publications," he said.

"They should improve the supervision mechanism for Internet information and strictly prevent obscene information from spreading online," Zhou said.

The anti-pornography office and Internet regulation authorities jointly declared war against online obscenity on Sunday, as part of a wider campaign to tighten the grip on the Internet. The campaign will last until November.

During the campaign, authorities will crack down on important Internet portals that are suspected of running obscene information, and those responsible will be held criminally accountable or transferred to the disciplinary inspection department for investigation, according to Zhou.

People who post pornographic articles online for profit can be charged with crimes of producing and distributing obscene materials, which can lead to sentences of up to three years in prison, according to a judicial explanation issued in 2004.

Individuals who pocket more than 250,000 yuan ($40,000) from publishing pornographic articles, defined as a serious violation of the law, can face life imprisonment and confiscation of their personal property.

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