London police said they had been called to the street event but the crowd refused to engage with officers.

“The event continued and more officers attended the scene and the group became hostile towards officers,” the police said.

Unverified images on social media showed crowds confronting officers and attacking a police car. Reuters was unable to independently verify those images.

Police said 15 officers were injured, none seriously although two required hospital treatment, and a small number of police cars were damaged.

“Last night we received numerous concerns from residents complaining about a large gathering, noise, anti-social behaviour and violence, and officers responded to those concerns,” said police Commander Colin Wingrove.

“These gatherings are unlawful, as well as posing a risk to public health and against coronavirus restrictions. The violence shown towards officers is totally unacceptable and we will not tolerate it in any form.”