As China gears up for the Beijing Olympics next September it's under growing pressure over its human rights record.

In Xinjiang province, home to tens of millions of ethnic minority Uighurs, authorities have been accused of carrying out a campaign of intimidation. And human rights groups say Uighur culture is at risk of being eroded by the dominant Han Chinese.

China correspondent Charlotte Glennie reports.

Charlotte Glennie: Once a week, traders, villagers and nomads converge at the Illi Sunday animal market. It's a place to socialise and do business. Animals are usually the most valuable possession a family owns. Donkeys and horses are still a popular form of transport. And being here is like stepping back in time.

This is thousands of miles from Beijing in both distance and mindset.

Xinjiang's ethnic Uighurs have been traders for centuries. The market's a lively place, but a sense of sadness also lurks among these Muslim descendants of the Turks. Human rights organisations say it's because the Uighur people are oppressed abused and discriminated against by the Han Chinese.

Xinjiang is one of the most sensitive regions in China. To understand why you have to look back on its turbulent past.

China claims Xinjiang's historically part of its territory, but it was only annexed to China in the 18th century. Many Uighurs believe they're living under colonial rule. A core group is fighting for independence, and they've been proclaimed paramount enemies of the Chinese state.

One way authorities have responded to the threat is with the mass migration of Han Chinese into Xinjiang, much the same as the Hanisation of the neighbouring region of Tibet.

Han Chinese have brought their own culture and traditions into Xinjiang. In 1949, they made up less than a 10th of the region's population. Now they stand at more than 50 per cent, and their numbers are growing.

”Xinjiang has a population of 20.5 million, with 47 nationalities who live together like a big family.” Hu Wei

Hu Wei, Deputy Chairman, Uighur Autonomous Region (translation): Xinjiang is a sound and stable society of national unity, consolidated border defences and people of all ethnic groups living in peace. Xinjiang has a population of 20.5 million, with 47 nationalities who live together like a big family.

Charlotte Glennie: The Uighurs Arabic-like script coexists with Chinese Mandarin on street signs. But by and large, Xinjiang's 8 million Uighurs live separate lives to their Han Chinese countrymen.

Uighurs usually eat Halal Uighur food. The regional specialty is homemade bread and mutton. They try to shop in Uighur-owned shops. They attend Uighur schools. They even operate on a different time zone. Officially, the sun rises here at 8am. But Uighers run on Uighur time, two hours behind Beijing time, which is meant to apply across China.

With their own unique culture, customs and language, the Uighurs seem to have more in common with their neighbours in central Asia than they do with the Han Chinese. Human rights groups say Uighur culture is in danger of being submerged.

Dr Terry Narramore, lecturer, University of Tasmania: There's heavy scrutiny and surveillance of people who are considered independent of the state-endorsed process. So this, I think, is the key problem in terms of development of the religious freedom and cultural practices of the people in the area.

Charlotte Glennie: Resentment at Chinese rule is fuelled by perceived economic discrimination. Most of the major companies in Xinjiang are owned by Han Chinese and they largely employ Han Chinese. Uighurs are sparsely represented within government departments.

Many young Uighur people we spoke to told us it's very hard to find work. Rapkat Abdul is one of the few who'd be interviewed on camera. He chooses his words carefully.

”To be honest, it's difficult to find a job for young people.” Rapkat Abdul

Rapkat Abdul: To be honest, it's difficult to find a job for young people, but it's easy [for those] who study for a while, very good, it's easy to find job. But one thing he must know China very well. But [if] he don't know China very well they cannot find job, especially in China, I think. Or [if] his or her parents very powerful, he have the money, he can also find job.

Charlotte Glennie: Over the decades, frustration has pushed Uighur separatists to detonate bombs and carry out attacks. Tension peaked 10 years ago here in Yining, when dozens were killed and injured in clashes with police.

The Chinese government claims Xinjiang separatists are terrorists with links to al-Qaeda. This video released in March shows the al-Qaeda deputy Ayman al-Zawahiri mentioning East Turkistan - the Uighur resistance name for Xinjiang - in parallel to oppression in Iraq, Afghanistan, Palestine, Chechnya and Somalia.

In January, China raided what it said was a terrorist camp in the south of Xinjiang, killing 18. But some accuse China of inflating the terrorist threat as an excuse to wage its own internal war on the separatists.

In 2005, it's reported more than 18,000 Uighurs ended up in jail for endangering state security. Their crimes ranged from being labelled terrorists to talking to foreign reporters.

Xinjiang's Muslim call to prayer isn't allowed to be broadcast over a loudspeaker. The Chinese government tolerates the Uighurs' religious beliefs but it imposes strict controls on the way Islam is practised.

Abdul Kayum, Yili village imam (translation): Under the leadership of the Government, the Muslim people carry out their affairs, do what they must do, study the Koran. The party also carries out the policy, helps people, doesn't forbid people their beliefs.

Charlotte Glennie: Abdul Kayum's been leading prayers in the small village mosque for more than 30 years. He says the village's original 200-year-old mosque was torn down.

Abdul Kayum: We had no strong feelings at that time because we were going to get a new mosque. It was impossible to keep the old one as well. So we didn't say anything.

Charlotte Glennie: Our Uighur guide wouldn't translate some of the more sensitive questions we'd asked the imam, like what life was like here after the Yining riots or post-9/11.

”We're not getting enough information about exactly what's going on in the region.” Dr Terry Narramore

Dr Terry Narramore: Clearly, we're not getting enough information about exactly what's going on in the region and this is partly a result of government control, party controls. But, generally speaking, people are not even allowed to openly discuss some of these things, in terms of a more autonomous position, more autonomous practice of their religion, establishing new mosques and so on and so forth. These are all strictly controlled in the Chinese context.

Charlotte Glennie: Xinjiang is one-sixth of China's land mass and it has what the country needs - abundant natural resources. Soon, this region will be China's top oil-producer. Xinjiang is of critical strategic importance to China because of its own vast resources and, also, due to its proximity to oil and gas-rich central Asia.

Just over the border here is Kazakhstan, where China is pouring money into oil investments. It's also building thousands of kilometres of new roads linking Xinjiang with its central Asian neighbours. The aim is to boost trade ties and improve living standards in this remote region. The new infrastructure is part of the Government's go-west strategy, aimed at transforming previously neglected places. The Government also hopes prosperity will dampen any aspirations of separatism.

Many Uighurs say they're yet to see the benefits.

Nurmemet, Uighur trader: Now, some people have no jobs, but they have to do something to make a living. There's no other way. If we don't do this, we would lead a terrible life. Unlike foreign countries, we don't have enough money given to us by the Government. We have no formal jobs, so if we don't do this, how can we live?

Charlotte Glennie: Poverty continues to pervade many Uighurs' lives, thousands are using heroin, unemployment is rife. A large number of Uighurs can't or won't speak Mandarin, even though it's costing them jobs.

Many centuries ago, the Uighurs dominated this part of the world. Now, many fear they're in danger of being swallowed up.