China shut down more than 60,000 pornographic websites this year, netting almost 5,000 suspects in the process, a government spokesman said on Thursday, vowing no let-up in its campaign against material deemed obscene.

Beijing has run a highly publicized drive against what officials said was smutty and lewd content overwhelming the country's Internet and cell phones, threatening the emotional health of children.

Critics accuse the Chinese government of deepening the crackdown, launched last December, and tightening overall censorship, and say that the push has netted many sites with politically sensitive or even simply user-generated content.

But Wang Chen, head of the State Council Information Office, or cabinet spokesman's office, said the offensive was vital.

Our campaign has been a great success and this has not been achieved easily, he told a news conference. We have made the Internet environment much cleaner than before as there was a lot of pornography available.

We have changed this situation and this has been well received by many sectors across society, Wang said. But our campaign has not come to a stop. This will be a long battle.

As long as there are people with bad motives who want to spread violent or pornographic information, we will have to continue our campaign to resolutely crack down on the spread of such information.

Of the 4,965 suspects, 1,332 people received criminal punishment with 58 jailed for five years or more, Wang said.

The government checked the content of 1.79 million websites and deleted 350 million pornographic and lewd articles, pictures and pieces of video footage, he said.

With an estimated 450 million Internet users as of the end of November, China has a bigger online population than any other country. Yet the government worries the Internet could become a dangerous conduit for threatening images and ideas.

China has blocked a number of popular websites and Internet services, including Google's YouTube, Twitter, Flickr and Facebook, as well as Chinese content sharing sites.

The government accused them of carrying content harmful to China's security and in breach of Chinese laws, including images of protests in sensitive regions such as Tibet.

Wang said he had seen media reports that Facebook's chief Mark Zuckerberg had visited China recently, but said Zuckerberg had not met his department, which oversees the Internet in China.

We saw reports that he met with some well-known figures in China's Internet industry. We are also still trying to learn more about his visit to China, he added.

Google Inc, the world's top Internet search engine, closed its China-based search service in March, two months after it said it would stop censoring search results in response to what it said was a sophisticated cyber attack that it traced to China and increasing limits on freedom of expression.

The dispute was resolved in July after Google changed the way it directs users to an unfiltered search engine. The case prompted a diplomatic row between China and the United States over web freedom.

(Reporting by Ben Blanchard, Sabrina Mao and Benjamin Kang Lim; Editing by Robert Birsel)

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