Chinese technology companies have begun the purging of several thousand user accounts in the wake of an announcement of a new rule that requires Chinese Internet users to use their real names for all their online accounts.

China's top Internet regulating body, the Cyberspace Administration of China (CAC), said on its website that Baidu, Weibo, Tencent, and Alibaba have deleted more than 60,000 accounts because of usernames that were misleading, promoted pornography, or had links to terrorist groups. Also removed were accounts that claimed to be owned by government agencies, such as "Buy License Plates," and accounts that encouraged people to "Come Shoot Guns." The companies also removed accounts that had sexually explicit avatars.

The CAC said Baidu, China's biggest search engine, deleted more than 23,000 user accounts from its PostBar discussion forums because of their "vulgar" usernames and avatars. Chinese social networking website Weibo removed 5,500 accounts, including accounts that shared information about the separatist group East Turkestan Islamic Movement, which has been blamed by China for violence in the northwestern region of Xinping, although some experts question the cohesive existence of such a group.

Tencent also deleted several accounts from its instant messaging and social media platforms, mostly those with usernames that promote gambling, firearms, fake invoices and fake food safety information, the CAC said. It is unclear if Alibaba deleted user accounts but the regulating body said Alibaba had established a new working group to deal with usernames.

The witch hunt comes as new rules by the CAC require all Internet users to use their real names to identify their online accounts. Although China has tried to enforce such restrictions in the past, the regulations, which will take effect on Mar. 1, come amid an intensification of China's online censorship system, also known as the Great Firewall, under President Xi Jinping.

Analysts have warned that requiring users to user their real names could be detrimental to Chinese Internet companies, which will have to deal with higher operational costs combined with a smaller number of users. However, companies believe the new rules serve to benefit their businesses.

"It's a vanishingly small percentage of the total number of Baidu PostBar accounts, which number in the hundreds of millions," said Baidu spokesperson Kaiser Kuo, referring to the 23,000 accounts deleted by the firm in line with the new rules.

Forrester senior analyst Xiaofeng Wang also said that as Internet marketers become more mature about their metrics, they start dismissing figures such as the total number of accounts and place more importance on the number of actual active users.

Still, China's username restrictions are wont to be criticized for creating barriers to freedom of expression. Blogger and venture capitalist Isaac Mao tells the Wall Street Journal that he fears the new rules will stifle creativity in the long run.

"It definitely has a chilling effect," Mao said. "In the long run, freedom of speech and freedom of innovation will be dramatically harmed."