SHANGHAI -- China’s Internet regulator summoned officials from the country’s two biggest Internet companies, Sina and Tencent, on Wednesday, after a video showing a young couple having sex, apparently in a fitting room at a Uniqlo apparel store in Beijing, went viral online in China.

In a case, which commentators said highlighted the gap between the tastes of Chinese Internet users and the government’s increasingly puritanical stance, the Cyberspace Administration of China (CAC) complained that the “vulgar video had spread like a virus,” and that it “clashed with socialist core values,” local media reported. The CAC ordered Sina, operator of the country’s biggest microblogging service Sina Weibo, and Tencent, which operates China's most popular social media app WeChat, to “fulfill their responsibilities” and cooperate with an investigation into the video, according to the Global Times.

One CAC official was quoted as noting that copying or publishing pornographic material was a crime in China, though no detail was given about whether Internet companies that had broadcast the film would face charges. But state media said that Internet users wanted the firms to “uphold their social obligations."

The one-minute film shows a man in a T-shirt and jeans first telling a naked woman to kiss him, and then filming their encounter on his mobile phone via the fitting room's mirror. It appeared online in China on Tuesday evening, and was widely reposted, before being deleted from some sites the following day.

Announcements on a loudspeaker in the background of the recording suggested that it was filmed in a Uniqlo store in central Beijing, and some Internet users argued that since the technical quality of the film was surprisingly good, it might have been set up by the company as a viral marketing scheme. Chinese media have reported that after seeing the film, many people came to the store to take photos there.

However Uniqlo used its own Weibo account to deny the report, and called on customers to "obey social ethics" and use fitting rooms "correctly." 

Chinese Internet users have also posted social media account details and other information about the couple involved, and identified the woman as a student at a Beijing university -- in a classic example of what’s known in China as an “online human search." However some Chinese media reports said that a number of people complained that they had been wrongly identified online as being one of the participants in the film -- and added that this case was another example of the pernicious effects of the Internet on society.

ChinaSexStore Chinese residents pass by Wenzhou City Adam & Eve Health Products Limited Company, one of the 100 or so "sex health product stores" in Wenzhou in the eastern province of Zhejiang. Photo: Reuters

The Chinese government has recently launched a campaign to clean up the Internet, calling for volunteers to denounce unhealthy content and promote "positive energy." Last week China's legislature published a draft of the country’s first ever Cyber Security Law, which would impose more pressure -- and financial penalties -- on website operators that failed to remove unhealthy content. The summoning of the nation's two most powerful websites by the CAC in the latest case may also be designed to show that the authorities are determined to “clean up” the web, which officials say has promoted the spread of "unhealthy western values," political as well as social.

The Chinese leadership, which is currently seeking to purge the Communist Party of corruption in an attempt to win popular support, also appears keen to purify public morality. Officials have pulled TV shows because they revealed too much cleavage, criticized “vulgar celebrities,” and banned scantily clad models from the country’s biggest auto show, and gaming and digital entertainment expo.

However the latest incident may be a reminder that social -- and sexual -- mores have changed rapidly in China in recent years, and the campaign to clean up public morality may have some way to go.

A social media account operated by the official People’s Daily newspaper lamented that while the New Horizons spacecraft was sending back unique images of Pluto after its nine-year journey, many of China's most lively minds were focused on the Beijing Uniqlo store.

And an opinion column in the Chinese edition of the Global Times newspaper, which is also published by the People's Daily, said the "Sexgate" incident showed that the nation was currently in an "era of gossip," where people believed that they could do whatever they want online. The author said he didn't know whether to "laugh or cry" at such cases -- and added that promoting the "positive energy" that the government is seeking online would be a tough challenge. But he said the authorities should be "patient and thoroughly innovative in our approach," in order to make this a reality.