The discovery near Xi'an of a Qin Dynasty tomb group, believed to be the largest in China, has delighted archeologists but also attracted the attentions of grave robbers.Excavations undertaken ahead of a railway improvement project in Shaanxi Province unearthed 604 tombs in Qujia Village, Lintong County."I was astounded by the sheer number of tombs," said Sun Weigang, a researcher with the Shaanxi Institute of Archaeological Research. "We know Shaanxi is rich in cultural relics, with over a thousand tombs unearthed every year. But we have never found so many in such a small area".Most of the tombs are of ordinary people and do not contain particularly valuable objects, but are of enormous interest to archeologists researching the social life of the period. A vast collection of pottery and bronze ware has been unearthed including cauldrons, pots, jars, axes and swords, as well as more than 200 complete human skeletons."The remains are mainly of adult men who died from natural causes. They don't appear to have had a close clan relationship with each other," according to Chen Liang, associate professor of Archaeology, Northwest University.Archaeologists hope the discovery of the tombs will help them locate the site of the ancient Qin Dynasty city of Liyi. It had been thought that Liyi was near a village called Liuzhai, based on sporadic discoveries of Qin relics. "But the tombs are over 5 kilometers away from Liuzhai Village, and the custom of the time was to locate burial grounds close to the city," an archaeologist said.It takes about a week for two or three workers and one technician to excavate a tomb. Local villagers have been employed on the dig because of the large number of tombs. "The digging is not difficult, but the cleaning work is very tough, and will take at least a year if not more," an excavator named Quan Xihong told reporters.The old men in Qujia Village knew there was an ancient city nearby. Villagers often found jars and pots in the fields but thought it was bad luck to take them home. Recently though, grave robbing has been on the increase.A local man said that while grave robbery wasn't a problem in Qujia, there were entire grave robbing networks in other, nearby villages. One of the site excavators said that he had personally come across grave robbers.