Chinese officials have stepped up monitoring of cyber cafes and video game halls as part of a crackdown against Internet pornography and violence.

More than 100,000 unlicensed cyber cafes were shut down over the past five years during a crackdown on Internet pornography and violence, state-run Xinhua news agency quoted an official of the State Administration for Industry and Commerce as saying.

Local authorities have raised the entry threshold for Internet cafes and stepped up monitoring of entertainment venues, especially cyber cafes and video game halls, to protect children, he said.

The number of Internet users in China reached 457 million last year.

Along with the growth of the net, China is also witnessing an explosion of micro bloggers, whose numbers were stated to be around 100 million already.

The micro-bloggers, mostly using their mobile phones emerged as a new media in China, challenging the hold of the tightly controlled state press which prompted the Chinese government to activate its firewalls to block critical content to prevent any anti government campaigns.

Some micro bloggers in China complained in the recent weeks that all information related to massive uprising in Egypt calling for ouster of President Hosni Mubarak has been blocked in the Chinese language Internet even though the English official media like CCTV and the newspapers covered the Cairo crisis.

Critics say that the blocking the content related to the crisis in Egypt in the Chinese Internet, which is used by the vast majority of Chinese was reportedly aimed at preventing the Cairo crisis from influencing the people here to challenge the one party rule of the Communist Party of China, (CPC).