Chinese prospectors have dug more than 20 holes at the site of an abandoned jade processing plant over the past year hoping to uncover gemstones, mainland media reports.
Some of the holes were up to two metres deep at the more than 400 square-metre site in Changping, a district in the northwest suburb of Beijing, the Beijing Youth Daily reported.
Residents hoped to uncover pieces of jade, crystal, agate and even highly prized calcite that were discarded while the plant was in use and sell them for large profits, the report said.
However, some residents said the things found in the ground were mostly just leftover bits and pieces of gemstones that were worth very little.
The owner of the former plant said he had been filling in the holes dug by treasure hunters for more than a year, but was unable to stop them returning and digging new holes.
The local authority has now arranged security on the site to prevent residents falling and injuring themselves while looking for valuables.
The head of the village committee, where the plant is located, said signs had also been erected to remind villagers to stay away from the site and stop digging.
A number of Chinese residents regularly go digging at construction sites in cities hoping to find valuable rocks and stocks.