When China’s Communist Party celebrates the 60th anniversary of its rule in October it will want to present to its people — and to the world — the image of a Government in control of a booming economy and an increasingly open society. The bloody riot by Muslim Uighurs presents a crucial challenge to this view.

China will want to hit back hard at those whose anger set off the violence. But it will also want to tell its increasingly well-informed people what happened — or, at least, as much as the propaganda mandarins feel can be told — without damaging the idea of national unity that is the party’s latest watchword.

The first news of the riots appeared within hours. But the reports late on Sunday did not represent a bold initiative by some outspoken newspaper or website — they came from the government mouthpiece. Beijing had decided to take charge of the story and to guide its coverage. In such a sensitive year and with the biggest National Day party in a decade only three months away, it was crucial to manage the news agenda.

Still raw in the memories of China’s leaders is the worldwide condemnation that followed last year’s rioting in Tibet. On that occasion state media took 24 hours to mention the violence, by which time international reports had presented the riot — in which Tibetans attacked ethnic Han Chinese, leaving 18 people dead — as a brutal crackdown by security forces.

The tale was more complicated, but China’s news blackout and the closure of the region to foreign reporters cast doubt on the accuracy of official reports.

China is discovering that few people are ready to give the benefit of the doubt to a Communist Party that rules in secrecy and brooks no challenge to its authority. In Tibet it disastrously lost the propaganda war. It regained sympathy after the Sichuan earthquake, only to see that dissipate after a few weeks with the arrests of activists who wanted to know why more schools had collapsed than government buildings.

This time things are different, but only up to a point. Less than 24 hours after Uighurs went on the rampage, state media revealed that 140 people had been killed. Such speedy disclosure is almost unprecedented and reflects the lessons learnt from the secrecy surrounding the Tibet unrest and from the openness in reporting the earthquake, which caused a worldwide wave of sympathy.

Li Changchun, China’s propaganda boss, told the heads of the media a few months ago that they must take the lead in reporting “bad” news if they were to retain control over how events were presented. They have heeded his call. Furthermore, foreign journalists are being let into Urumqi to see the damage for themselves.

But the limits to this openness are already apparent. There has been scant explanation of how 140 people were killed and more than 800 injured in a few hours of violence. Were all of them victims of angry Uighurs chafing at Chinese rule? State media has announced that the unrest has been brought under control. How? Residents said they heard gunshots: did security forces open fire to halt the rioters?

On October 1 President Hu will stand where Chairman Mao stood 60 years ago — on top of Tiananmen, the Gate of Heavenly Peace — and review a massive parade. It is an event that must be a success, and because of this China is still afraid of telling the whole truth.

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