The Metropolitan Police Commissioner has said assaults on officers at an anti-racism rally were “shocking and completely unacceptable” ahead of more demonstrations planned across the UK on Sunday.

Dame Cressida Dick said 14 officers were injured during clashes with a minority of protesters in central London on Saturday following a peaceful Black Lives Matter demonstration.

The force said 14 people had been arrested after tensions escalated while Dame Cressida said in a statement that there was “no place for violence” in the capital.

“I am deeply saddened and depressed that a minority of protesters became violent towards officers in central London yesterday evening,” Dame Cressida said.

“This led to 14 officers being injured, in addition to 13 hurt in earlier protests this week.

“We have made a number of arrests and justice will follow. The number of assaults is shocking and completely unacceptable.

“I know many who were seeking to make their voices heard will be as appalled as I am by those scenes. There is no place for violence in our city.

“Officers displayed extreme patience and professionalism throughout a long and difficult day, and I thank them for that.”

Sadiq Khan said that while the majority of protesters were peaceful, pockets of violence was “simply not acceptable”.

In a statement, the London Mayor said: “I stand with you and share your anger and pain. George Floyd’s brutal killing must lead to immediate and lasting change in countries, cities, police services and institutions everywhere. We must root out racism wherever it is found.

“The vast majority of protesters in London were peaceful. But this vital cause was badly let down by a tiny minority who turned violent and threw glass bottles and lit flares, endangering other protesters and injuring police officers.

“This is simply not acceptable, will not be tolerated and will not win the lasting and necessary change we desperately need to see.”

It comes ahead of more anti-racism demonstrations which are due to take place in London and across the country on Sunday.

A rally is scheduled outside the US Embassy in Battersea, south-west London, while an estimated 4,000 people are expected at a gathering in Bristol and demonstrations will also be held in Edinburgh and Glasgow.

Health Secretary Matt Hancock said it is “undoubtedly a risk” that there will be an increase in coronavirus cases following the protests.

He told Sky’s Sophy Ridge on Sunday he supported the protesters’ arguments, but urged: “Please don’t gather in groups of more than six people because there is also a pandemic that we must address and control.

“And so we’ve got to make the argument, we’ve got to make further progress, on top of the significant progress that has been made in recent years, but we’ve got to do it in a way that’s safe and controls the virus.”

Dame Cressida urged protesters to find “another way” of making their voices heard, rather than descending on the capital’s streets amid the coronavirus crisis.

“I would urge protesters to please find another way to make your views heard which does not involve coming out on the streets of London, risking yourself, your families and officers as we continue to face this deadly virus,” she said.

Police were out in significant numbers for the marches through London on Saturday, including outside the US Embassy, in protest against police brutality following the death of George Floyd in Minneapolis.

Demonstrations were carried out peacefully for much of the afternoon but disturbances began breaking out at around 6pm outside Downing Street.

Scuffles broke out when objects were thrown towards officers wearing protective gear, with mounted police called in to drive some of the demonstrators back along Whitehall.

Video footage appeared to show an officer colliding with a traffic light before their horse ran through a crowd of protesters, sending them scattering.

The Metropolitan Police later confirmed a female officer fell from the horse and had been taken to hospital. Her injuries are not life-threatening.

Metropolitan Police Federation chairman Ken Marsh said the officer had “quite nasty” injuries, telling BBC Breakfast: “She’s stable – she has some quite nasty injuries which she sustained. And the horse is fine.”

He added: “I think my colleagues – as always – were absolute heroes… the abuse they took. They tried to facilitate the public behaviour… I had nothing but pride in what I saw. It was horrendous seeing my colleagues being injured.”

Photographs showed the officer being treated at the scene as she lay injured on the pavement, while other images showed bikes being thrown at horses.

Officers are “investigating the full circumstances” of the officer’s fall but the force said the horse made its own way back to its stables nearby.

Elsewhere on Saturday, boxing heavyweight champion Anthony Joshua used crutches to join people on a peaceful protest in his home town of Watford.

Many people wore face masks and social-distancing measures were encouraged during events in Manchester, Cardiff, Sheffield and Newcastle, among other cities.