During the Islamic festival of Korban last April, when each household sacrifices a sheep, a bloody and dramatic event took place, which remained unreported. Nine regional separatists surrounded the country home of a local Uighur leader in the town of Kuqar. They threw a grenade through the window before storming the house. Finding the man inside with his wife, his younger brother and brother's wife, they cut out the tongues of all four and slit their throats. Thus the traitors were silenced.
The leader was accused of "letting down the Uighur people and failing to properly represent them". In other words, he was judged to be a tool of the Chinese government.
The army was at the scene almost immediately. Finding themselves surrounded, the nine men blew themselves up with grenades.
In the wake of the killings, official documents urgently recommended that the new railway planned to link Urumqi, the capital of Xinjiang, to Kashgar in the Uighur heartland of the south be completed within the next three years. Large numbers of Han Chinese - the dominant, "mainstream" Chinese - were to be moved into the area to stabilise unrest. The document warned: "So far we have been too soft on the locals. From now on, we will start to get tough."
The disturbance is just one of a growing number of outbursts of violence since the early Eighties, culminating in last month's riots in Yining when Uighur youths took to the streets, beating up Han Chinese and burning their bodies. Young Uighurs grow up with a keen hatred for the steadily increasing numbers of Chinese migrants.
A spokesman for Uighur exiles suggested last week that the death of Deng Xiaoping wouldbring a power struggle within the Chinese elite. He predicted: "If that happens, the independence movement in Turkestan will intensify." The Turkic-speaking Uighur nationalists want to establish an independent "East Turkestan" homeland.
Hundreds, sometimes thousands of Han Chinese arrive daily at Urumqi railway station laden with their life's belongings. Tensions erupt easily. An Uighur man who accidentally jostled a Chinese on a bus was told he was "filthy" and asked why he didn't "go off and get on his donkey cart?" The Uighur replied that he would love to, only he couldn't as the Hans had eaten all their donkeys. The apparently humorous exchange thinly veiled the cultural clashes and inequalities in the new society geared exclusively towards Hans. Not only is the Han Chinese love of pork considered "unclean" by Muslim Uighurs, but the Chinese tendency to kill and eat anything that moves is also abhorred. Uighurs are frequently known to quote the Hans' own saying when expressing their disgust: "Of things that fly, the only thing they don't eat is aeroplanes. Of things with four legs, the only thing they don't eat is tables."
The Uighurs regard the Han Chinese as introverted people who fail to share their passions for music, dance and hedonism.
As the social structure changes, opportunities have become few and far between for Uighurs. The hundreds of Han migrants arriving daily in Xinjiang are lured by government incentives of housing and jobs. The Chinese are building new residential areas, but it is rarely the Uighurs who get to live there. Job discrimination is routine: when an Urumqi academic fluent in Chinese approached a computer firm and offered his services, he was told: "We hadn't considered Uighurs."
While Chinese-imposed birth control remains a bone of contention for rebels in the strongly Islamic south, social inequality and discrimination in the labour market is the main catalyst of ethnic opposition among intellectuals in the modernising north of Xinjiang. So who will be the champions of the cause for Uighuristan, the long-awaited homeland of the once-nomadic Muslim Uighurs?
The older generation are too scared of the repercussions and of a return to worsened poverty and famine. They still bear the scars of Mao Tse-tung's Great Leap Forward and the Cultural Revolution. They shrink from the anger growing in their children and look on anxiously. In the words of one Uighur: "Young people are unable to look ahead. We older ones can see things in the long term, we're not so impetuous."
It remains to be seen whether the younger ones can overcome traditional disagreements between oasis towns, and between north and south. A migrant worker from Aksu living in Urumqi believes they can: "When it comes to the crucial hour, Uighurs will come together."
Meanwhile, long lines of Chinese army trucks rumble regularly along country roads between Aksu and Baicheng deep in the south. In Xinjiang, nobody forgets who is in charge.