No YouTube and Yahoo in China amid Tibet Riots

In an apparent attempt to censor international coverage of the violence that is unfolding in the Tibetan capital Lhasa, the Chinese government has closed down access to several of the world's most popular websites.

The popular video sharing site YouTube has been blocked within China to prevent viewers seeing images of the protests and the army's brutal response. Also the news pages of famous internet portal Yahoo! have been made inaccessible.

The entire Guardian website has been closed down and there have been severe restrictions to accessing coverage of recent events in Tibet on sites like Times Online.

The photo-sharing website Flickr, Wikipedia, and the US newspaper LA Times are among the other sites to which access has been cut off.

Popular sites which incorporate news from different sources such as Google News have been subjected to 'keyword filtering', where a Chinese internet user attempting to load a page which contains words such as 'Tibet' or 'Dalai Lama' will see the site stall.

There have also been reports that the editors of some of the most popular 'forum' or bulletin board sites in China have been directly contacted by government officials and told not to publish any content relating to the recent protests.

As if blocking the websites was not enough, there are also reports that Internet cafes have been closed ensuring that there is minimum internet access. Land line telephone and mobile phone services have also been disrupted by the authorities.

According to a CNN video, foreign media have been banned from Tibet. Television news reports by CNN and the BBC were periodically cut during the day. Also no foreigner has been allowed to enter Tibet since the middle of last week. So there are very few foreign witnesses left in the region to witness the unfolding repression.

The Chinese authorities appear to have taken a page out of Myanmar's book but only more efficient. Last September, the Myanmar regime had cut internet access in and out of the country after several days of graphic coverage by local activists.

Censorship is made easier in China by the fact that the country has relatively few internet service providers (ISPs) - the gateways through which all Western content must pass before it is seen from within China - meaning that software which runs 'keyword' checks on sites can readily be installed.