Picture shown is for illustrative purposes only.
Those at Friday's event became violent and threw projectiles at police as they entered an estate at Havelock Close in West London, the police said in a statement.
"Officers encountered bricks and other missiles being thrown at them," police said, adding that the gathering was eventually dispersed with no arrests.
"We are aware of injuries to seven officers as a result of the hostility."
Such gatherings were illegal and presented a risk to public health amid the virus outbreak, they added.
A dispersal zone has been authorised in the area, for which police have received stop and search powers.
The protesters were ostensibly venting their anger at the government’s Police, Crime, Sentencing and Courts Bill, which is currently going through parliament. Under the terms of the bill, which covers England and Wales, police will be able to put more controls on protests.
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