The biggest gathering was at Naval Row in Poplar where around 1,000 people turned up to take part in an unlicensed music event.
Seven people were arrested and each face a £10,000 fine under coronavirus regulations for organising the event after officers arrived shortly before midnight on Saturday.
Another 200 people took part in another unlicensed event at Rothbury Road in Hackney before it was also halted by officers, who confiscated the sound systems.
Other unlawful parties included Halloween gatherings in Acton Cemetery and Ruskin Park in Camberwell, as well as a christening celebration on Tottenham’s High Road where police said one person was reported for a £10,000 fine.
Met Commander Ade Adelekan said: “If you think the next few days are an excuse to break the rules, think again. You will get caught, we will take action and impose the maximum sanctions.”
