Officers were called to a property in Green Street, Mayfair, at 1.30am on Sunday morning to reports of an illegal party taking place at a flat.
They found 50 people inside and the party’s organiser, a 29-year-old man, was fined £10,000 for breaching lockdown rules.
The others in attendance were issued with 50 fixed penalty notices of £800 each.
Police were then called out to another illegal gathering at another flat in nearby Brooks Mews at 2am.
Officers found 20 people breaking Covid restrictions at the property and they were all were issued with £800 fines, although the party’s organiser is yet to be identified.
“Despite recent announcements about how and when Covid restrictions may be eased, nothing has changed in terms of the regulations,” said Inspector Kevin Fagan, of the Central West Command Unit ,which covers Westminster.
“Illegal gatherings like this are irresponsible and put pressure on the emergency services who have do deal with the consequences of these people’s selfish actions.
“The rules are clear, as should be the message that the police will enforce them where wilful breaches are found to have taken place.”