XI'AN - Police in Shaanxi province have detained eight people suspected to have looted a complex of ancient graves dating back more than 2,000 years.

Police in Luonan county, Shangluo city were tipped off early last month that a complex of graves in a mountain on the outskirts of the county seat had been ransacked, a spokesman with the Shangluo Municipal Public Security said.

The graves, dating back to the Spring and Autumn Period (770 BC - 476 BC) and the Warring States Period (475 BC-221 BC), been under provincial-level protection since 2003.

Local police found the tomb raiders had excavated a number of holes in the graves and some gloves left by the robbers at the site, the spokesman said.

After more than 20 days of investigation, police found and detained the eight suspects in neighboring Henan province, he said.

Police are further investigating the case, he added.

Shaanxi, as the hometown of Qinshihuang, the first emperor of a united China, is well known for its numerous historical places of interest and cultural relics.