Officers were called to reports of a disturbance at a residential property in The Works, Withy Grove, Manchester city centre, at around 12.30am last Sunday.
Greater Manchester Police said they found around 50 to 60 people inside a two-bedroom flat, and none of them were social distancing or wearing face coverings.
Music was being played through a sound system which included commercial-sized speakers.
After reviewing the evidence, police issued a £10,000 Fixed Penalty Notice (FPN) on Friday to the organiser – a 38-year-old man – for contravening the requirement not to hold, or be involved in the holding of, a gathering of more than 30 persons in a private dwelling.
Superintendent Chris Hill said organising this flat party was “a clear act of non-compliance which put those in attendance at risk of Covid and could, ultimately, increase demand on the NHS”.
Elsewhere, four people were issued with fines of £200 each after Kent Police officers broke up a party of around 20 people at a flat in Canterbury.
Kent Police said the illegal gathering at the property in Adelaide Place was dispersed at around 1.30am on Thursday – the same day new national lockdown came into force in England.
Officers issued £200 FPNs to two men and two women who were all in their early 20s and organised the party.
Assistant Chief Constable Claire Nix of Kent Police said: “Hosting large gatherings in the middle of a pandemic, especially on the first day of a new national lockdown, is completely unacceptable and we do not hesitate to take action against those who display such blatant disregard for the coronavirus regulations.”
Justice Secretary Robert Buckland said this week he supported clamping down on the “tiny minority” of people who are not willing to obey the lockdown and said there would be increased fines for repeat offenders.
His comments came after police chiefs warned people who ignore coronavirus restrictions to be prepared to “face the consequences of greater levels of enforcement”.
There is a £200 fine for every breach, which doubles with every offence up to a maximum of £6,400, as well as £10,000 for large gatherings.
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