Large anti-racism demonstrations across UK
The protests, sparked by the death of George Floyd in america, were held in cities including London, Manchester, Cardiff, Leicester and Sheffield.
In London, protesters knelt for a minute's silence before chanting "no justice, no peace" and "black lives matter".
A lot of the day's protests were calm but in the evening there have been disturbances outside Downing Street.
BBC home affairs correspondent Tom Symonds said the protest was largely over when missiles and fireworks were thrown at a police line.
Police horses were used to regain control, but one horse galloped ahead and its own rider fell to the bottom after hitting her at once a traffic light. Her injuries aren't life-threatening, the Metropolitan Police said.
Fourteen people were arrested and 10 officers were injured after a smaller group became "angry and intent on violence", the force added.
In a tweet, Mayor of London Sadiq Khan told the protesters "I stand with you and I share your anger and your pain" and said the tiny minority of folks who became violent "let down this important cause".
The protests went ahead despite officials advising against mass gatherings due to coronavirus.
Home Secretary Priti Patel said the social distancing advice was "for the safety of most folks", while Met Police Commissioner Dame Cressida Dick said the protests were "unlawful".
Thousands of men and women gathered in the administrative centre, the majority donning face coverings and many with gloves.
Some held signs made mention of coronavirus, including one which read: "You will find a virus greater than Covid-19 and it's called racism".
Meanwhile, in Northern Ireland, police said that they had issued "a substantial number" of fines given the dangers of crowds in the pandemic.
Protests began in america after a video emerged of Mr Floyd, a 46-year-old black man, being arrested by four officers on 25 May in Minneapolis.
Videos showed Mr Floyd, who was unarmed and in handcuffs, dying after a white policeman knelt on his neck for practically nine minutes. The footage - seen all around the world - showed him gasping that he cannot breathe.
An officer has been charged with murder while three of his colleagues stand accused of aiding and abetting the killing.
At a protest in his hometown of Watford, Britain's world heavyweight champion boxer Anthony Joshua told the crowds: "We are able to no longer sit back and remain silent upon this senseless, unlawful killing and sly racism on another individual."
In central London, protesters dropped to 1 knee and raised their fists in the air beyond your US embassy amid chants of "silence is violence" and "colour is not a crime".
Sarah Law, a 27-year-old train manager, said there is a "great atmosphere" at the protest in London. She said: "I don't want my future children to experience what I've. It's time for us all to unite together irrespective of our race and operate for what's right."
Meanwhile, in Glasgow, anti-racism campaigners renamed streets which have links to the slave trade, replacing street signs with the names of enslaved Africans, black activists and victims of police brutality. Demonstrations are scheduled in Glasgow, Edinburgh and Aberdeen on Sunday.
In Manchester about 15,000 protesters gathered at Piccadilly Gardens in the location centre, clapping together and holding placards bearing the initials BLM.
They gathered despite warnings from Greater Manchester Mayor Andy Burnham that mass gatherings were "risky" after fears coronavirus may be spreading rapidly again.
Elsewhere, several hundred persons marched in Newcastle, even though many more took part within an online protest organised in the north-east of England.
More protests occurred across Europe on Saturday and others have begun in the US capital of Washington DC.
Meanwhile, police in Northern Ireland said organizers of the protests in Belfast and Londonderry will be reported to the general public Prosecution Service with a view to prosecution.
Organizers in Belfast had marked out social distancing measurements. PSNI Assistant Chief Constable Alan Todd said regulations should be honored as "they are not ordinary times".
