The Chinese government took steps during 2006 to increase its control and monitoring of internet access by the country's growing internet population, the US Department of State said in a human-rights report released on Tuesday.

"While the government continued to encourage expanded use of the internet, it also took steps to monitor its use, control content, restrict information, and punished those who violated regulations," the annual report said. Among the steps implemented by the government are stricter requirements for website registration, greater official control over content, and a wider definition of what constitutes illegal activity online, it said.

The Country Reports on Human Rights Practices are published annually by the State Department's Bureau of Democracy, Human Rights and Labor.

China has nearly 140 million internet users, according to the China Internet Network Information Centre (CNNIC), which tracks internet usage in the country. The large number of users has not eroded the government's ability to control access to content it deems undesirable, said the State Department, citing reports that the Chinese government employes "tens of thousands of persons" to monitor the internet.

"The authorities reportedly began to employ more sophisticated technology enabling the selective blocking of specific content rather than entire websites. Such technology was also used to block emails containing sensitive content," the report said.

The Chinese government has also enlisted the help of domestic and multinational companies to restrict access to information on the internet. "Chinese search engines such as and the China-based search engines of Yahoo, MSN and Google filtered search results, including those relating to the Voice of America, Radio Free Asia, and human rights," it said.