In a Sunday disclosure, Lee Kai-fu - the ex-head of Google's China division - said that he had been censored on two Chinese microblogging sites, Sina Weibo and Tencent Holdings, for three days because he had been using microblogging services to complain about state controls over the Internet.

Lee, who is an influential Chinese Internet executive, recently revealed on the Twitter microblogging site - on which he has approximately 1 million followers - that, for a three-day period, he was banned from posting on the Sina Weibo and Tencent social networking sites on which he has 30 million followers.

Criticizing the Chinese government for its tight control of the Internet, Lee - who earlier ran Google and Microsoft's China operations - recently complained about the government's censorship of GitHub, a site for sharing open-source code popular with developers.

Despite the fact that it is till not clear as to who had ordered the ban on Lee, it is being widely speculated that the Chinese government is probably behind the move, given the fact that it heavily limits Internet access inside the country.

Inviting his 30 million followers on Sina Weibo and Tencent to follow him on Twitter, Lee said in a Twitter post: "I've been silenced on Sina and Tencent for three days, so everyone can come here to find me." Incidentally, even though Twitter too is blocked in China, it is believed that circumnavigating that control is quite easy.