LONDON — A number of British police officers were injured Saturday as far-right activists faced off with anti-racism protesters in cities and towns across the country, following a stabbing rampage at a dance class earlier this week that left three girls dead and several wounded.

With dozens of similar gatherings taking place around the country this warm and sunny weekend, police have mounted a significant security operation, deploying thousands more officers onto the streets, many in riot gear. Police have also made more prison cells available and are using surveillance and facial recognition technology. Court hours have also been extended to judge those arrested.

On Saturday, Merseyside Police said a number of officers were injured in “serious disorder” in the center of Liverpool, about 20 miles away from the scene of the stabbing attack in the seaside town of Southport in the northwest of England.

In a series of posts on the social media platform X, the police force, that covers Liverpool and Southport, said there is “no place for this despicable behaviour which disrupts the lives of members of the public who live in the city, or are visiting to enjoy the amenities the city has to offer.”

And Humberside Police in a statement said three police officers have been injured and four people arrested following disorder in Hull, a city in the northeast of England. Earlier, windows of a hotel in Hull that is used to house migrants were smashed.

Police also said they had made multiple arrests in Bristol, which is arguably the most left-wing city in the U.K, during a standoff that saw as right-wing activists heavily outnumbered by their opponents.

“Some of the behavior we have seen is completely unacceptable and we will use all the powers available to us to deal with it,” said Avon and Somerset Police, which oversees the city.

Elsewhere, bricks were thrown at police officers in Stoke-on-Trent in central England while scuffles have also been reported in Belfast, Manchester and Nottingham. In Blackpool, a seaside town near Southport, punks, in the town for a festival, were seen clearing up the mess left after rioting by far-right activists.

There were no reports of far-right marches in London. Separately, thousands of pro-Palestinian demonstrators marched peacefully through the city to protest Israel’s military operation in Gaza.

Britain’s new Labour Prime Minister Keir Starmer held a crisis meeting with ministers on Saturday, in which he said police have the government’s “full support” to take action against “extremists” attacking officers and attempting to “sow hate,” according to his office in No. 10 Downing Street.

The latest outbreaks of violence come a day after protesters in Sunderland in northeast England tossed beer barrels and rocks at police officers. A car and the building next door to a police station were set ablaze, and 12 people were arrested.

The violence erupted earlier this week, ostensibly in protest of Monday’s stabbing attack in Southport. A 17-year-old male has been arrested.

False rumors spread online that the young man was a Muslim and an immigrant, fueling anger among far-right supporters. Suspects under 18 are usually not named in the U.K., but Judge Andrew Menary ordered Axel Rudakubana, born in Wales to Rwandan parents, to be identified, in part to stop the spread of misinformation.

In a press briefing on Saturday in Sunderland, Northumbria Police Chief Superintendent Mark Hall described Friday’s violence as “unforgivable,” saying four police officers were injured, three as a direct result of the disorder. He also said a mounted rider sustained serious injuries in an accident and is receiving treatment in hospital.

“During the course of the evening, our officers were met with serious and sustained levels of violence,” he said. “Make no mistake, if you were involved last night, expect to be met with the full force of the law.”

Police said many of the actions are being organized online by shadowy far-right groups, who are mobilizing support online with phrases like “enough is enough,” “save our kids” and “stop the boats.” Counter-protests are also anticipated with the organization Stand Up To Racism.

Far-right demonstrators have held several violent gatherings since the stabbing attack, clashing with police Tuesday outside a mosque in Southport — near the scene of the horrific stabbing — and hurling beer cans, bottles and flares near the prime minister’s office in London the next day. Many in Southport have expressed their anger at the organized acts of violence in the wake of the tragedy.

The attack Monday on children at a Taylor Swift-themed summer dance class shocked a country where knife crime is a long-standing and vexing problem, though mass stabbings are rare.

Rudakubana has been charged with murder over the attack that killed Alice Dasilva Aguiar, 9, Elsie Dot Stancombe, 7, and Bebe King, 6. He has also been charged with 10 counts of attempted murder for the eight children and two adults who were wounded.

Starmer has blamed the violence on “far-right hatred” and vowed to end the mayhem. At a news conference Thursday, the prime minister said the street violence was “clearly driven by far-right hatred” as he announced a program enabling police to better share intelligence across agencies and move quickly to make arrests.

Home Secretary Yvette Cooper, who is responsible for law and order issues, said the “bottom line here is we cannot stand for this kind of thuggery or criminal disorder on our streets.”