Officers attempting to disperse crowds at an unlicensed music event have been attacked by revellers, police said.
Scotland Yard said objects have been thrown at officers dispersing the crowd at an event at Colville Gardens, Notting Hill.
It comes after “appalling scenes” of violence at a street party in Brixton on Wednesday evening.
Kensington and Chelsea Police tweeted: “Officers are at the scene of an unlicensed music event near Colville Gardens, #W11.
“Objects have been thrown at officers dispersing the crowd. Violence will not be tolerated & units are responding appropriately.
“This gathering is illegal & we ask anyone in attendance to leave.”
Scotland Yard said in a statement on Facebook late on Thursday that its officers were undertaking an “enhanced policing operation” across the capital.
Commander Bas Javid said extra officers, clad in personal protective equipment, had been called in to ensure there was an “effective and prompt response to any reports or disorder”.
He added: “Our role is to keep our communities safe and this evening people can expect to see a heightened police presence out in areas where we know these events are taking place.”
“This is in direct response to concerns expressed by our communities, many of whom were scared and shocked by the events taking place outside their homes.”
Meanwhile, police also attended an “unlicensed music event” at Streatham Common on Thursday evening.
The force tweeted: “Officers are currently at Streatham Common where an unlicensed music event is taking place.
“They have engaged with a large number of those in attendance and the crowd has now almost entirely dispersed.”
Extra police officers in protective gear were dispatched to illegal raves planned around London following “appalling scenes” of violence at a street party in Brixton on Wednesday.
The Met Police said it was targeting further unlicensed music events and block parties around the city after 22 officers were injured on the Angell Town estate in Brixton.
Footage on social media showed police vehicles smashed and officers pelted with bottles during clashes with a large crowd, with Downing Street condemning the scenes as “appalling” and Home Secretary Priti Patel calling the incident “utterly vile”.