Chinese police raided an alleged terrorist camp in a western mountain region near the border with Pakistan, killing 18 suspects and arresting 17, a police official said Monday.

Song Hongli, director of the general office of the Xinjiang Public Security Bureau, said the raid occurred Friday at a training camp run by the East Turkestan Islamic Movement, or ETIM.

One police officer was killed and another was injured in the shoot-out, Song said.

Police are searching for suspects who are believed to have escaped during the raid, Song said, but did not say how many.

Police found 22 grenades and material for 1,500 more, he said.

Song said the camp was located in the Pamir Plateau, a sprawling high-altitude section of China's Xinjiang Autonomous Region near the borders of Pakistan, Afghanistan and Kyrgyzstan.

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Song did not give an exact location.

China has long claimed that militants among the region's dominant ethnic Uighurs are leading a violent Islamic separatist movement in Xinjiang. The Uighurs are Turkic-speaking Muslims with a language and culture distinct from the majority of Chinese.

Critics accuse Beijing of using claims of terrorism as an excuse to crack down on peaceful pro-independence sentiment and expressions of Uighur identity.

Chinese troops occupied Xinjiang at the end of the communist revolution in 1949, shipping in millions of Chinese migrants and interfering heavily in Uighur religious affairs.

Chinese authorities say ETIM is one of the region's most violent groups, labeling it a terrorist organization and alleging that it has links to Al Qaeda.

The United States has also put ETIM on a terrorist list.

Two years ago, China claimed that Muslim separatist groups and individuals in western China had carried out 260 attacks since 1995, killing 160 people and injuring 440.

Diplomats and foreign experts, however, say that many of the bombings and other violence China has linked to the group actually stem from personal disputes.

About two dozen Uighurs were captured by U.S. forces in Afghanistan following the Sept. 11, 2001, attacks.

China has demanded their return, but the United States fears they might face persecution there. Five Uighurs were sent to Albania last year after no other countries would accept the men.

China often paints a contradictory picture of the security situation in Xinjiang.

Officials seem eager to show they are cracking down on what they consider to be anti-government activity, but they also sometimes deny terrorist activity in the region, apparently wanting to portray it as safe for development and international investment.