Parliament Square
One MP said the curbs on civil liberties would "make a dictator blush".
Self-proclaimed 'statue defenders' were filmed hurling glass bottles, fireworks and smoke grenades at police on Saturday.
A planned Black Lives Matter rally has been cancelled amid fears of clashes between groups.
Brexiteers partied in Parliament Square as the UK's 47-year membership to the EU came to an end.
'Democracy is an ongoing process, it is not a one-off event.'
Police were aware both protests had been planned for central London on Saturday.
The protest saw a giant blimp modelled on Boris Johnson fly in Parliament Square on Saturday.
Shadow foreign secretary is "recovering" after accident in Parliament Square.
As President Trump continues his second state visit with a banquet at Buckingham Palace, protesters took to Parliament Square for a people’s banquet.