Pic: AP.

Some of WeChat’s highest profile public accounts were shut down or suspended yesterday, most likely part of the China’s sweeping crackdown on online content.

At least a dozen accounts were shut down or suspended yesterday, with “no apparent forewarning.” Anyone clicking on affected accounts was greeted with a pop-up message saying the account had been shut for “violating regulations.”

Some of the accounts were operated by popular news outlets and columnists, such as Luo Changping and Xu Danei – who alone boasted an estimated 200,000 subscribers – ensuring the blocking of the accounts will have an immediate impact. (China Digital Times has published a partial, translated list, showing at least 39 WeChat accounts were shut down or suspended).

China’s Internet Police – the State Internet Information Office – had previously targeted rival microblog Sina Weibo, with over 100,000 accounts deleted, and some high-profile and outspoken microbloggers jailed for “spreading rumours.” Users have fled Weibo in droves in recent months, and its loss is WeChat’s parent company Tencent’s gain: the China Internet Information Centre said 37 per cent of users who quit Weibo last year started using WeChat.

A big part of WeChat’s success – and what sets it apart from Weibo – is the way it allows users to communicate in small, private circles of friends. It limits the size of ordinary chatrooms to 40 people, and public pages, which users can subscribe to, can only post one message a day. This limits the speed of dissemination and has – until yesterday’s crackdown – largely deflected the attention of censors.

“WeChat is less of a potential threat to the authorities than Weibo is,” one of the founders of the anti-censorship site GreatFire.org, who goes by the pseudonym Martin Johnson, told Reuters.

The censors paid more attention to “cleaning up” Weibo than WeChat, he said, because of the speed at which information – or misinformation – can spread to its 280 million users.

Still, WeChat was always in the censors’ purview. An analysis last year of messages on WeChat that revealed the platform was being closely monitored by censors – alarmingly, even beyond China’s borders.

In September 2013, China’s Supreme People’s Court issued a guideline that threatened up to three years jail time for microbloggers who posted messages the government deemed slanderous, if those messages exceeded 5,000 views or 500 reposts or shares.

Wen Yunchao, an outspoken Chinese blogger and media analyst based in New York, said the blocking of WeChat accounts was likely the first action taken by a working group on Internet security headed by President Xi Jinping, which met for the first time on February 27.

During a speech in November, in which he mentioned WeChat by name, President Xi said “online communications and national security has already become a conspicuous problem standing before us.”

“[The government] waits for a new medium to gain a certain level of influence and then they crack down,” Wen said.

For its part, Tencent said it took the action “to safeguard the user experience.” In a statement to Hong Kong-based media group iFeng, a spokesperson said WeChat “strictly prohibits” what it called “malicious marketing,” as well as pornography, violence, and “political rumors. It was unclear how long the block would last.

WeChat already boasts more than 100 million users outside China, but the censorship could affect the app’s aggressive – and expensive – expansion into the US, Europe and Africa.

Chinese diaspora groups around the globe may be accustomed to the frustrations of censorship, but the mere threat of interference by the Chinese government could be enough to discourage potential users elsewhere.

In an increasingly competitive OTT (Over The Top) app market, rivals like Line (based in Japan), Viber (Cyprus/Israel) and Whatsapp (USA) will be hoping it does.