Police have made an arrest, after more than 3000 people attended an illegal rave near Bath over the weekend.
Officers were called to the former Charmy Down airfield, Upper Swainswick, at 23:21 GMT on Saturday 18 July.
They closed approach routes to the event, but people abandoned their vehicles and walked in.
Avon and Somerset Police says the "dark and wet" meant that it was too risky for public health to immediately close the rave.
There were also 120 calls made to 999 that night, all needing an immediate response.
Officers had stopped another unlicensed music event taking place in the Frome area earlier in the evening.
The music was stopped by 13:00 GMT on Sunday 19 July, with the majority of the site cleared three hours later.
A group, trying to continue the event in an adjoining field, was then dealt with by officers.
People miles away from the site reported hearing the rave - some claiming their windows were vibrating.
Chief Superintendent Ian Wylie said: "We’re sorry for the disruption caused to so many residents.
"It’s frustrating that we are having to pull officers away from our 999 response to deal with the selfish actions of the organisers of this event and those attending it.
“They knew full well the disruption this would cause and the ongoing risk to public health of large gatherings due to COVID-19.
"We brought officers in from their rest days and called on support from neighbouring forces to close down this event".
Around eight 999 calls were also made to the ambulance service from the rave.
Police say the suspect refused to leave the event when asked, they also seized five vehicles and other equipment.
Anyone with relevant information is asked to call police on 101, quoting reference 1414 of 18 July.