The spark that set off the tinderbox relationship between Han Chinese and ethnic Uighur Muslims in China’s far west was lit by violence at a toy factory 2,000 miles away. That those clashes, which left two workers dead and several injured, could have sparked the deadliest riot the country has seen in decades underscores the antipathy between the two ethnic groups.

But it also highlights how China’s kneejerk control of the media to ensure that only the minimum of bad news reaches its public can breed mistrust, rumour and overreaction.

Late last month a rumour at the Xuri Toy Factory in the southern town of Shaoguan in China’s industrial heartland that Uighur workers had raped two young Han Chinese employees triggered a backlash. Han workers attacked their Uighur colleagues. Two Uighur men died and dozens of Han and Uighur were injured.

Within days officials announced that the “rape” was a rumour put about by a disgruntled former employee - who was now in police custody. A total of 13 people, all Han, were arrested.

For Chinese officials, who made public the detention of the rumour-monger, the incident seemed to be over. Uighurs had access to the facts.

But the damage was done. Word reached Uighurs in their homeland in the westernmost Xinjiang region. Rumour was rife. Local people heard that hundreds of their fellow Uighur had died. Others murmured that Uighur children had been chopped up. Anything seemed credible after all resentment between the groups has bubbled in Xinjiang for decades.

China’s people have grown accustomed over the decades to treating official reports with some suspicion. What has been left out? What details glossed over? Even if the state media report was correct, it was clearly enough to arouse unhappiness festering just below the surface. Uighurs resent an influx of Han following job opportunities offered by development of oil and gas fields in Xinjiang. Many feel that these riches should belong to them and not the incomers. Many resent the limits placed on their religious practice: for example, the ban on anyone under 18 attending mosques.

The tales from the south were enough to transform Uighur grumbles into full-blown violence.

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