Es Police were called to an illegal gathering of around 400 people partying in a woodland in the village of Margaretting at the weekend, reports Es Live.
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The event is said to have started around 10:30pm and rolled through to the early hours of the morning. Local residents reported seeing close to 100 cars parked along the nearby Cock Lane, with the police believing the attendees to have travelled from outside of Es.
Police attended the scene but considered it to offer little threat, harm and risk to those in attendance and local residents.
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Chief Inspector Steve Scott-Haynes, District Commander for Chelmsford and Maldon, said: "I'd like to thank local residents for their patience last night and throughout the early hours of this morning.
"We believe that this event was held and attended by people from outside of the county and our enquiries are ongoing to locate the people responsible for organising it.
"To anyone thinking of hosting, or attending, an illegal rave or unlicensed event - know that you're committing criminal offences and could face prosecution. During this time, you are putting people's health and safety at risk, and undermining the hard work of our NHS staff."
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