Fierce competition among Chinese museums, private institutions in particular, is fueling a new wave of tomb raiding, according to a leading historian.

Ni Fangliu, whose research has led him to make the acquaintance of some of China's most prominent collectors and many tomb raiders, said museums almost never turn down the chance to buy antiques, even those acquired through dubious means.

"The number of antiques passed down through the generations is set and unchangeable now. So you don't have to guess where 'new arrivals' on the antiques market come from."