Under the Protection of Badgers Act 1992, it is an offence:
For more information see the full Protection of Badgers Act 1992
If you see anyone with dogs and equipment (spades, nets etc) at or near a badger sett, try to observe their activities. Note their appearance, type and number of dogs and any implements used.
Look for any vehicles and note type, colour and registration numbers.
Notify this information together with an accurate location IMMEDIATELY to the police by telephoning 999.
DO NOT TACKLE DIGGERS OR LAMPERS, LEAVE IT TO THE POLICE.