Chinese government officials have pledged to forcibly crack down on separatists in its far western Xinjiang province after three years of continuous unrest that has killed hundreds of people.

Zhang Chunxian, Communist Party secretary of the Xinjiang committee, threatened to use iron fists in the region, according to the Xinhua news agency.

We should leave terrorists no place to hide, he said.

In 2009, deadly riots erupted in the capital city of Urumqi between the native Uighurs and the Han Chinese who have been migrating to the remote westernmost part of China in large numbers since 1949, when Beijing seized control of the province.

The Uighurs are Turkic Muslims who have long accused China of religious and political repression; they also fear that large-scale immigration of Han Chinese into their homeland will erode and dilute their unique culture.

Western human rights group including the British-based Amnesty International, has condemned China’s brutal policies in Xinjiang.

The general trend toward repression that we see all over China is particularly pronounced in Xinjiang, said Catherine Baber, Amnesty’s Asia-Pacific director, in a statement.

Amnesty also cited that the activities of Chinese security forces during the July 2009 riots in Xinjiang leave many unanswered questions, with respect to the number of people who actually died and how. Since that time, Beijing has heightened security in the area.

The Chinese government hopes to stabilize Xinjiang by directing money at the problem, but without a credible independent investigation of the Urumqi riots and underlying grievances, resentment and mistrust will continue, said Baber.

Instead of stifling inquiry, blaming outside agitators and generating fear, the Chinese government should use the anniversary to launch a proper investigation, including into the Uighur community’s long-simmering grievances that contributed to the unrest.”

Amnesty estimates that more than a 1000 people were detained in the wake of the July 2009 riots, with hundreds more having “disappeared.”

Chinese officials have countered that the separatists in Xinjiang are “terrorists” and have possible links with al-Qaeda in Afghanistan and Pakistan.