Eight illegal raves have been broken up by Sussex Police since the start of lockdown.
Three of them took place in Brighton, while others were discovered in Hastings, Lewes, Plumpton, Petersfield, and Friston Forest.
But despite hundreds of people attending some of the raves, police confirmed only one person was arrested, according to data obtained from a Freedom of Information request.
Officers have also yet to fine anyone involved, despite being given new powers to hand out fixed penalties of £200 to people flouting Covid-19 rules, which double for every subsequent offence up to a maximum of £6,400.
However, equipment including speakers, a generator, a woofer and an amp was seized from the illegal rave in Friston Forest as the organiser fled the scene.
The news comes as Sussex goes into the Tier 2 restrictions today – the second highest alert level in place for areas with “higher or rapidly rising infections”.
Police say they are monitoring social media and working with landowners to try and reduce the risk of illegal raves taking place and extra resources will be deployed where necessary.
“They are often organised through other means, particularly simple word of mouth and that is why we need local people to be alert to the possibility and signs of a rave taking place in their area,” said a spokesperson.
“Although there are powers available to the police to close down illegal gatherings such as this, before exercising these powers an assessment has to be undertaken to determine whether or not such a gathering can be closed down safely and effectively.
“This includes consideration of the timing of the event and the layout of the land.
“We’d also like to remind the public that we will continue to engage, explain and encourage people to follow the government guidelines on coronavirus, and enforcement action will be taken if necessary.”
Darrell Gale, director of public health at East Sussex County Council, said: “Putting East Sussex in the ‘high risk’ tier for coronavirus reflects the uncomfortable truth that cases here are still rising quite steeply rather than coming down, as they are in England as a whole.
“For months we’ve had one of the lowest infection rates in the country.
“But we’ve never been insulated from the risks of Covid spreading rapidly in our community and we’re at a point where that may be starting to happen, with 136 cases per 100,000 of population over the last seven days.
“This is still below the national average, but it won’t stay that way unless we act now to reverse the upward direction the virus is taking in East Sussex.
“All of us have responsibility for what happens next.”
He urged people to avoid crowds, reduce their travel and social contact as much as possible and if they must meet others do so outside.
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