The number of Internet users in China, already the world's largest online market, hit 477 million at the end of March, a senior government official was quoted by state media as saying Monday.

The official from the Telecommunications Administration Bureau, which falls under the Ministry of Industry and Information Technology, announced the figure at a meeting in Beijing, the official Xinhua news agency reported.

The number of people using the Internet in China had hit 457 million at the end of 2010, meaning that more than one-third of its 1.3 billion-strong population were online.

China's spiralling online numbers have turned the Internet into a forum for citizens to express their opinions in a way rarely seen in a country where the traditional media is under strict government control.

The growing strength and influence of the web population has prompted concern in Beijing about the Internet's potential as a tool for generating social unrest, and authorities have stepped up surveillance in recent years.

The government blocks web content that it deems politically sensitive in a vast system dubbed the "Great Firewall of China".