Researchers in Carnegie Mellon University's School of Computer Science analyzed millions of Chinese microblogs, or "weibos," to uncover a set of politically sensitive terms that draw the attention of Chinese censors.

A Chinese government official was quoted by state media as saying on Monday that the number of Internet users in China hit 477 million at the end of March.

According to official figures released Thursday, China's Internet population has grown to 420 million.

Google changed tack in China on Tuesday in order to address government complaints about its attempt to evade censorship, as it vied to get its business license renewed in the country.

On Tuesday, China defended its action taken to censor the Internet, saying it needed to do so in order to ensure state security.