English Heritage says there have been a number of incidents of people illegally using metal detectors and taking artefacts from land at properties it owns in Wiltshire.
It's thought most are searching for Iron Age artefacts.
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Another cold and frosty night lies ahead, but the winter sunshine prevails for Friday.
Staying cold and frosty with plenty of winter sunshine.
Plenty of sunshine for some, but a little more cloud in the east and feeling cold