Google has announced that its video-sharing service YouTube has been blocked in mainland China.

Chinese authorities seem to have started blocking the site days ago, but only yesterday, after traffic ground to a halt, did Google officially admit that the site was indeed being blocked.

BBC News and Reuters report that the service was blocked because it was hosting video of Chinese soldiers beating Tibetan monks. China's state news agency Xinhua said that supporters of the Dalai Lama had in fact fabricated a video depicting Chinese police officers brutally beating Tibetans in Lhasa.

YouTube also hosts other videos that could be seen as objectionable by Chinese authorities, such as footage of the Tiananmen Square massacre in 1989.

Web censorship is on the rise in China. Earlier this year authorities embarked on a programme to block sites with pornographic content, but many critics point out that China's battle against porn has often been used to silence dissidents without causing as much negative publicity as its usual 'harmonization' policies.

More here.