The censoring began at 5pm local time on Tuesday as access to sites was blocked, though users could still reportedly reach some of them through proxies, VPNs and third-party desktop clients.
The blocked sites include Twitter, Flickr, and Microsoft's Hotmail, according to the Telegraph. FoxNews added the Huffington Post, Life Journal and MSNs Space blogging tool to the list. BBC viewers in China also saw their screens black out when the news service broadcast stories about the anniversary, and foreign news crews have been barred from filming in the square. Readers of the Financial Times and Economist magazine found stories about Tiananmen ripped from their pages. Authorities also plan to begin cracking down on unapproved internet cafes, according to reports from state media.
The blocked sites are just a few among thousands that China's censors have targeted since the beginning of last year as a string of anniversaries is marked, including the 50th anniversary of the Tibet uprising. In April, access to YouTube was blocked after someone posted images of China's military police beating Tibetan monks.
Twitter became popular in China after last year's earthquake in Sichuan when people used it to get out reports of the devastation and signal news of their safety to friends and family members. The Times of London recently noted that Chinese users of Twitter can write terms that would normally be blocked if they typed them on other web sites, such as "6/4″ for the date of the Tiananmen massacre or "Charter 08," referring to a document published online last year by a group of intellectuals that calls for greater freedom and democracy.
As a result, the Times says, bloggers have been anticipating the blocking of Twitter.
"Twitter is a new thing in China. The censors need time to figure out what it is," blogger Michael Anti told the China-based blog Danwei.org. "So enjoy the last happy days of twittering before the fate of YouTube descends on it one day."
He noted that given the nature of the Chinese language, a Chinese tweet could crowd in much more meaning in the 140 characters allowed by Twitter per message, than can English users. "140 Chinese characters can make up all the full elements of a news piece with the '5 Ws' (Who, What, Where, When and HoW)," he said. "But the joy of the Chinese Twitterland is more fragile, and I hope that it will live longer in this country."
