ALMATY, Kazakstan (AP) _ Tucked away in a remote corner of the globe, Muslim separatists in western China have chafed at Beijing's rule for decades in a quest for autonomy largely hidden from the outside world.

But Beijing could not keep a spate of deadly riots and bomb blasts quiet, and one of China's most volatile ethnic problems _ just across the border from the Central Asian republic of Kazakstan _ is receiving attention at a time when the Communist leadership is particularly sensitive to disturbances.

At least 10 people were killed in riots this month in China's western Xinjiang region, and separatists also are suspected in the bombings of three public buses Tuesday in the Xinjiang regional capital of Urumqi.

``There are lots of people engaged in separatist activity out here,'' said an official at Chinese government-run Xinjiang television who gave his name only as Zhang. ``This is the work of bad elements.''

The separatists want autonomy for the Uighurs (pronounced WEE-gers), an ethnic group that accounts for two-thirds of Xinjiang's 16.6 million people.

The bus bombings, which came on the last of six official days of mourning for Chinese leader Deng Xiaoping, killed at least two people and injured 27. They seemed carefully planned and suggested that anti-government groups were becoming more organized and sophisticated.

The separatists always have felt their best chance of gaining independence would be at a time of turmoil in China, when authorities are preoccupied with other political events. They are watching the current leadership transition to see if it brings any instability.

China considers Xinjiang off-limits to foreign journalists, making it virtually impossible to accurately report events or gauge the mood. Most information comes from residents reached by telephone, most of whom speak on condition of anonymity.

But some Uighur separatists have migrated to Kazakstan, a former Soviet republic bordering western China that has a sizable Uighur minority. In Kazakstan, Uighurs can speak out against Chinese rule.

``We have nothing in common with the Chinese in terms of religion, culture, or language,'' said Kakharman Khozhamberdi, president of the Regional Uighur Association in Kazakstan.

The Uighurs are a Muslim, Turkic-speaking people who have never assimilated with the majority Han Chinese. China's Communist rulers have controlled Xinjiang (pronounced syin-jyahng) since they came to power in 1949, quashing a brief period of Uighur autonomy that had lasted for five years.

The Uighurs have sought to regain that status for almost a half-century, and there have been periodic bursts of unrest, but little prospect of success.

The separatists won some room to maneuver in 1991 with the breakup of the Soviet Union. The creation of five new, mostly Muslim states in Central Asia has led to the reopening of the long-closed border with China.

Today, there is a booming trade among Uighurs, who cross back and forth across the China-Kazakstan border, selling their goods at huge, outdoor markets. The growing contacts and influence of Islam have increased talk of autonomy.

``If we had weapons, we would already be in Xinjiang,'' claimed Modan Mukhlisi, spokesman for United National Revolutionary Front, a Uighur separatist group in Kazakstan. ``If we had weapons, we could raise 10,000 men here in Kazakstan overnight to go and fight for our freedom.''

Such statements appear to be mostly bravado, but the Chinese government has grown increasingly nervous and cracked down on the separatists last year following a security accord with Kazakstan.

Uighur groups in Kazakstan claim more than 50,000 Uighurs were arrested last year in western China, though the figure cannot be independently confirmed.

Growing numbers of ethnic Chinese have been moving into the sparsely populated territory, a development the Uighurs see as a Chinese attempt to dilute their way of life.

In Kazakstan, meanwhile, the Uighurs have been disappointed by the lack of support they've received from the Kazak government, which has said repeatedly it will not interfere in what it considers an internal Chinese affair.

Central Asian governments are far more interested in building trade ties with their powerful neighbor than becoming mixed up in the long-running ethnic feud.

Kazakstan and the other Central Asian countries ``all know what is going on, but they choose to close their eyes,'' said Yusupbek Mukhlisi, leader of the United National Revolutionary Front.