At around 1.30am on Sunday, 28 February, police received a call regarding an illegal gathering taking place at a flat in Green Street, W1.
Officers attended and found around 50 people present.
The organiser of the event, a 29-year-old man, was identified and was reported for a £10,000 fine for breaching Covid regulations.
A further 50 £800 fixed penalty notices were handed to those in attendance.
While dealing with this incident, police received a call at around 2am to another illegal gathering taking place at a flat in Brooks Mews, W1.
Officers attended and found 20 people gathered at the property – all were issued with £800 fines. Work continues to identify the organiser of the event.
Inspector Kevin Fagan of the Central West Command Unit which covers Westminster said: “Despite recent announcements about how and when Covid restrictions may be eased, nothing has changed in terms of the regulations.
“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.”