China blocks YouTube over Tibet riots
China's censors have tried to stem the flow of information from Tibet reaching the outside world and also block foreign news from their own citizens.
The government blocked the YouTube video sharing site within China, to prevent viewers seeing images of the protests and the army's brutal response. Any internet search for a website containing references to Tibet had already been censored.
A Tibetan journalist covering his homeland from neighboring Nepal, who asked to be identified as Lhuboom, said: "At this stage I think it's really difficult in Lhasa to use the internet at all."
Internet cafes have been closed, so while the internet may not have been blocked altogether there is little public access.
Land line telephone and mobile phone services have also been disrupted by the authorities, while there are widespread fears of phone-tapping for those still able to make calls.
"People suspect that the Chinese government are listening to their phones, so they don't talk, they are afraid," Lhuboom added.
No foreigner has been allowed to enter Tibet since the middle of last week. As tourists flock to leave the region, there are fewer foreign witnesses to the unfolding repression.
Television news reports by CNN and the BBC were periodically cut during the day, and the screens went black during a live speech by the Dalai Lama carried on the networks.
In a sign the authorities were preparing for trouble, foreign journalists were ordered out of the Tibetan parts of Gansu and Qinghai by local police, who told them it was for their safety.