Fireworks thrown in 'unprecedented' Bristol violence
Police officers suffered suspected broken bones as angry scenes unfolded in Bristol city centre.
"It's really unprecedented violence," said the chairman of Avon and Somerset Police Federation Andy Roebuck.
Crowds had gathered for the Kill the Bill demonstration in opposition to the Police and Crime Bill.
Campaigners have staged a string of protests against the bill, which would give the police more powers to deal with non-violent demonstrations.