Officers arrested 23 suspected drug dealers and three people on suspicion of breaching anti-social behaviour orders in the first stages of the operation.
More arrests are expected in the coming days.
Commander Alison Newcomb from Westminster borough said:
"Drug dealing on the streets of the West End or in any part of London can not and will not be tolerated. Put quite simply, if you are coming to the West End to buy or sell drugs, you need to think again."
More top news
A cyclist who ploughed into a mother-of-two has been cleared of manslaughter but convicted of "wanton and furious driving".
Women in Tower Hamlets can expect to live for 30 years in ill health, compared to just under 12 years for men in Enfield.
Travel website Lonely Planet has included Tooting, south London, in its list of the globe's must-visit locations.