A fake news story about sales of steamed dumplings stuffed with meat-flavoured chopped-up cardboard has triggered a far-reaching crackdown on Chinese journalists. A television reporter has been arrested and the media have been ordered to stop reporting most bad news.

The scandal has even forced China’s top official in charge of propaganda to make a rare self-criticism. Li Chang-chun, a member of the nine-man ruling Standing Committee of the Communist Party Politburo, made the behind-closed-doors apology as part of a purge of the media after the Beijing Television report last month. Such self-criticism is rare and could mark an internal humiliation for Mr Li as the party prepares for its 17th Congress in the autumn, when a new Politburo will be appointed.

Zi Beijia, a temporary reporter for Beijing Television, was arrested after it emerged that he had concocted a report in which steamed pork dumpling-makers soaked cardboard in caustic soda to soften it and then flavoured it with pork juice to make the bun filling. The report was a sensation, emerging when China is facing international criticism for exports of substandard or tainted food products.

However, the ramifications after it was revealed that Mr Zi’s report had been carefully choreographed have been even greater.

Other Chinese journalists said that it was not clear what charges Mr Zi would face, but they could include disturbing public order and spreading terror reports, both of which could mean that he faces several years in jail.

Mr Zi’s story has had immediate consequences for his colleagues, already operating in a media arena tightly controlled by the state and its propaganda authorities. Reporters at leading television stations, all of which are state-controlled in China, have been required to write lengthy self-criticisms of up to 2,000 words to show that they have learnt from Mr Zi’s case. Those whose self-criticisms still fail to pass muster after a second effort will be required to undergo strict re-education classes.

At least six senior executives at Beijing Television, including the head of the station, have been reprimanded, received demerits or been dismissed. The station made an unprecedented on-air apology for the fake report.

Eager to limit bad news in the run-up to the Party Congress, at which a new generation of leaders could emerge, the party publicity department, the State Administration of Radio, Film and Television and the State Press and Publication Administration have issued a circular to all news departments saying that anyone who causes public anxiety or tarnishes China’s image would be harshly dealt with or even prosecuted.

The order will make it even more difficult and dangerous for enterprising journalists, such as the reporter who broke the news that illegal brick kilns were employing children and slave labourers, to publish their work.

The dumpling report is far from the first hoax to make it into print or on to the small screen in China. In 2006 a newspaper reported that street peddlers were injecting sugared water into watermelons to boost profits. A year earlier a newspaper published a story citing a Chinese businessman as saying that water from Lake Baikal, in Russia, would be imported to Beijing. And last March a newspaper said that banana trees in southern China had been infected with “banana cancer”.

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