URUMQI, Aug. 5 -- Chinese archaeologists have discovered a huge 2,000-year-old tomb complex in northwest China's Xinjiang Uygur Autonomous Region.

The 100-plus tombs of various designs are scattered across 6 hectares of land in Kazak Autonomous County of Mori, said researchers with the Institute of Archaeology under the Chinese Academy of Social Sciences.

The tombs are believed to have been built by nomadic tribes that have roamed the area for 3,000 years. Horse skeletons have been unearthed from the tombs, and some large tombs were surrounded by piles of rocks, said Wu Xinhua, head of the excavation team.

Wu said many tombs had been damaged, as local villagers picked stones from the tombs to build houses after mistaking them for ancient military fortress sites. Archaeologists have begun excavation to prevent further damage to the sites.