Suspected class A drugs and what police believe to be pistol bullets were seized during a lightning raid on a house on the Clem Attlee Estate in Fulham.
Riot officers and dogs stormed the home, in John Smith Avenue, on Friday morning and made three arrests.
A carrier bag containing the suspected drugs was hurled out of a window as police entered the home, but was later discovered in the back garden.
Officers struck after building up intelligence on the property, which they believe is at the centre of a recent rise in antisocial behaviour and drug dealing.
In the past fortnight officers have seized a knife from and been attacked by people linked to the property, which is run by Notting Hill Housing Group. Just two people are registered as living there but it is believed a group of about 20 are using it as a base for drug dealing and antisocial activity.
Sergeant Sean McMahon, leading the operation, said the raids were a success. "I'm very happy with the result. The decent residents on this estate have been saying they're sick to death of this anti-social group, who have been getting bolder and braver and effectively taking over. They've been openly dealing drugs in the play areas."
Sgt McMahon believes gangs ignore regular beat officers and thinks raids are the only way the message can get through.
"It's the same old, same old when they see safer neighbourhood teams – they just laugh. The other day one of them said 'we own this estate, not you'. It's unbelievable."
Sgt McMahon hopes the raids are just the start of a major clampdown. "We hope there will be some follow-up to this in the form of issuing ASBOs, for example, to other people linked to the property.
"Rest assured we are doing what we can to make life better here."
