Cultural heritage experts are urging managers of historic sites to recruit more volunteers to keep watch over China's priceless relics.

The call comes shortly after centuries-old stonemasonry at Beijing's Ming Tombs was badly damaged by suspected would-be thieves.

Although many sites already have cameras and barriers, expert He Shuzhong warned that the general lack of awareness among the public and administrators about the importance of relics is a threat to their preservation.