(Reuters) - Use of microblogging in China quadrupled in 2011 compared with the previous year, with nearly half of all Chinese Internet users now taking to the near-instant service to gather news and spread views, a government Internet think tank said Monday.

Microblogging, or Weibo as it is known in China, allows users to send short messages of 140 characters or less to their followers. Twitter, the most popular microblogging platform in the world, is blocked by China's censors.

Sina Corp and Tencent Holdings both run popular Weibo platforms in China, both firms claim to have more than 200 million users.

Last year was a watershed year for Weibo with major events such as the Wenzhou high-speed train crash in July fuelling intense discussion on the platform.

The vibrant discussion and rapid dissemination of information on Weibo caused hand-wringing within the Communist Party, which fears that losing control of information and opinion could threaten its authority.

In December, city governments announced rules to regulate microblogging operators, requiring new users to register with their real names.

The total number of Weibo users rose 296 percent to 249.9 million in 2011, data from the China Internet Network Information Center (CNNIC) showed, meaning nearly half of the Chinese Internet population used Weibo.

CNNIC said in its report that by the end of December, there were 513 million Internet users in China, representing an Internet penetration rate of 38.3 percent. (here

.pdf) Another spot of high-growth in the Internet sector was the group-buying industry that saw a 244.8 percent user growth in 2011, bringing the total to 64.7 million users at the end of December.