Until a few months ago, it looked like 2009 would be a good year for Google in China. In the first quarter the company's share in the world's largest internet market by users had jumped above 30 per cent for the first time, breaking the psychological barrier of half of the market share of Baidu, its dominant rival.

Now Google is having a rude awakening. China's authoritarian government, caught up in a trial of strength with internet users over censorship, has opened a witch hunt on Google China.