In Hong Kong, tens of thousands of people have held a wake to commemorate the events that took place twenty years ago today in Tiananmen Square in the Chinese capital Beijing.

On 4 June 1989, the Chinese authorities cracked down sharply on a student protest in the square. Official reports said 241 people had been killed, but activists involved in the protests say there were thousands of victims.

In Beijing, the square remains open to the general public, but hundreds of police officers have been deployed to prevent disturbances. Ten years ago, it was completely closed on 4 June.

The Chinese state-owned media are silent about the issue. Television broadcasts of US news channel CNN and the BBC are being partly censored by the Chinese authorities and websites such as the social networking service Twitter and the photo-sharing service Flickr have been blocked.