An unlicensed music event involving around 30 people has been taking place in woodland near King's Lynn.
Police have said they are currently at the scene of the event, which is believed to have started in the early hours of this morning, at Bawsey.
A number of vehicles are also involved and officers are looking to close the event in a safe and controlled manner.
A police spokesman said: 'Enquiries will be carried out into establishing who the organiser(s) are with a view to prosecute, and will also deal with any offences committed.
'Whenever possible Norfolk Constabulary will seek to take positive action, seize equipment and prosecute offenders in line with the wishes of communities that are affected by such illegal activities.'
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