British historians hope to crack down on "nighthawking"

English Heritage and the British Museum are pushing for legislation to curtail the illegal use of metal detectors to discover and remove artifacts from private sites.

The practice is called "nighthawking". According to the Telegraph story, "[I]llegal searches at protected historical sites, the removal of items without permission from landowners or the failure to declare valuable finds - is being fuelled by the internet, which allows criminals to make thousands of pounds selling jewelry and ancient coins."