On Thursday 2nd June 2009 it will be the 20th anniversary of the Tienanmen Square massacre when an undisclosed number of student protesters were killed after tanks rolled into squash the protests. You might imagine, then, that in China services such as Twitter would be a-buzz with talk about the day. Well it probably would have been, had the Chinese authorities not closed it down on Tuesday.

Various chatroom sources are saying that both Twitter and Hotmail have been blocked throughout the mainland of China since 5pm on Tuesday, China time. There have also been some reports of Windows Live and Flickr being unavailable.