China's Communist Party has set out to curtail social networking following years of unfettered growth after its top committee issued an edict launching a new drive to control open messaging.
Websites such as Sina Weibo, a Chinese version of Twitter, have been allowed to grow explosively, with 400 million Chinese posting opinions and sharing information.
The Central Committee of the Communist Party, a 300-strong body of party, state and army leaders, has signalled its alarm that there is no equivalent to the Great Firewall that marshals the internet. It has promised to ''strengthen the guidance and administration of social internet services and instant communications tools'' to ensure ''orderly dissemination of information''.
Anyone spreading ''false rumours'' was threatened with stern punishment.
Chinese censors have struggled to keep pace with the websites. As quickly as they delete individual messages, they find they have already been spread by hundreds, or thousands, of others. ''It has been said that China maintains strict control over the internet, but it is actually quite difficult,'' Liu Yunshan, the head of the propaganda department, said in September.
Two events appear to have convinced China's leaders that the websites cannot be allowed to continue unchecked.
The government was deeply alarmed by the way the internet was used to galvanise the Arab Spring protests across the Middle East. It is also jittery about the ''Occupy'' movement that has been sweeping the West.
Sites such as Sina Weibo, which was launched in 2009, just after China banned Twitter, have quickly become part of the mainstream.
In response to government pressure, Sina has hired 1000 staff to monitor the flow of messages through its servers.
Yin Hong, a professor at Tsinghua's journalism and communications school, said the central government found Weibo a valuable way of gauging public opinion.
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