LONDON — The British capital was tense Wednesday as police, fearing a possible outbreak of the right-wing rioting that erupted elsewhere in Britain in recent days, flooded into several neighborhoods with large immigrant populations.

But the handful of anti-immigrant demonstrators police encountered in neighborhoods like Finchley and Harrow were vastly outnumbered by hundreds of counterprotesters carrying signs that said “Refugees Welcome” and “Racists Out, Refugees In.”

And in the east London neighborhood of Walthamstow, an even larger gathering of more than 5,000 anti-right protesters chanted “Love, not hate” while hundreds of police officers kept watch.

More than 1,000 officers were deployed throughout the city Wednesday, said Andy Valentine, deputy assistant commissioner of London’s Metropolitan Police Service.

Most of the protests and counterprotests occurred without any major incidents, Valentine said.

“I want to thank our communities for coming together across the capital and for showing community spirit this evening,” he said.

Police did encounter “anti-social” behavior in Croydon from a small group who were unrelated to the protests. The group was intent on “causing trouble,” Valentine said.

Overall, 10 people were arrested in Croydon, the south London town, including one person accused of assaulting an emergency worker and four accused of violent disorder, police said. Four people were also arrested in Waltham Forest, including two accused of weapons offenses that included a knife and a golf club, while another person was arrested in Hounslow and accused of possessing a weapon, police said.

There were also large and peaceful protests in support of refugees Wednesday in the cities of Birmingham, Sheffield, Southampton, Liverpool, Newcastle and Bristol.

“I’m here to stand up for human rights,” Jones Percival, 25, a plumber, said in Finchley. “I don’t believe in fascism. People of all colors and creeds are welcome.”

While Percival spoke, like-minded protesters began chanting, “Say it loud, say it clear, refugees are welcome here!”

One of the anti-immigrant protesters in Finchley was carrying a St. George’s Cross flag, England’s national flag, which is regularly flown by far-right groups. Police quickly confiscated it.

Another anti-immigrant protester, who identified himself as Paul and said he was 55 and from north London, said “I think this country is at boiling point” and blamed the French for not stopping asylum-seekers from reaching the British shore.

“I don’t care what color you are, but this country has become a soft touch,” he said. “We pay the French to stop the migrants, but they turn a blind eye to the asylum-seekers coming to this country. We need to stop them. We voted for Brexit to stop this, and it hasn’t happened.”

Violence broke out across the country last week after three young girls were killed in a knife attack at a Taylor Swift-themed dance class in Southport, in northwest England.

Fueled by false rumors that the suspect was a Muslim asylum-seeker, right-wing mobs attacked hotels housing asylum-seekers, as well as mosques and libraries, resulting in hundreds of arrests.

The suspect in the deadly stabbing attack, Axel Rudakubana, 17, was born in the Welsh capital, Cardiff, and lived for years in a village near Southport, police said.

King Charles, who along with Queen Camilla said in a statement after the deadly stabbings that they were “profoundly shocked,” has asked to be updated daily about the evolving situation.

Earlier Wednesday, London Mayor Sadiq Khan confirmed that officials were aware that specific locations in the British capital could be targeted and issued a pre-emptive warning.

“Anyone thinking of spreading hatred and fear in our city: if you break the law, action will be taken against you,” he said in a statement posted online. “Acts of violence and disorder on the streets of London will not be tolerated.”

While the owners of dozens of businesses in north London boarded up windows and shuttered doors, Mark Rowley, the chief of the Metropolitan Police, told reporters that thousands of officers had been deployed to protect potential targets like immigration law specialists.

“We’ll protect those people,” Rowley said. “It is completely unacceptable, regardless of your political views, to intimidate any sector of lawful activity, and we will not let the immigration asylum system be intimidated.”

Some north Londoners said they felt trapped between competing political currents.

“My problem here is you have two things that have been hijacked,” said a 44-year-old resident who said his name was Isaac and described himself as a “proud” British Jew. “The far right has hijacked the deaths of those poor little girls.”

But some of the people who are sticking up for the migrants are also antisemites who equate Zionism with racism, Isaac said.

“They said in advertising for this event that they wanted to get rid of Nazis, fascists and Zionists,” he said. “That scares me a little.”

The actions of the police in London mirrored the security operations taken over the weekend elsewhere in Britain.

Thousands of officers, many in riot gear, were sent out into the streets to deter protesters from showing up. More prison cells were made available in case they were needed. And law enforcement readied its surveillance and facial recognition technology to identify suspects. 

In the meantime, the courts in London adjusted their hours to make sure judges would be available in case the system was flooded with freshly arrested suspects.

In Merseyside, near Southport, three men were jailed Wednesday and accused of taking part in what police called a violent disorder, and several hundred more people were arrested.

Police said many of the actions were being organized online by shadowy far-right groups, who are garnering support online with phrases like “save our kids” and “stop the boats,” referring to small vessels, often rubber dinghies, carrying asylum-seekers across the English Channel from France. 

Tommy Robinson, founder of the far-right English Defence League, was among the first to call for nationwide protests, urging his 800,000 X followers to “hit the streets.” He recently fled Britain, where he was facing contempt of court proceedings.

Other online personalities, such as internet influencer Andrew Tate, who remains in Romania as he prepares to stand trial on sex trafficking charges, falsely claimed in a video on X that the knife attacker who killed the little girls was an “illegal immigrant.”

Tech billionaire Elon Musk, who owns X, further fanned the flames by claiming that the U.K. was on the verge of “civil war” after more than a week of right-wing riots.

Prime Minister Keir Starmer’s office quickly rebuffed Musk’s remarks, saying in a statement that such comments had “no justification.”

The riots have become one of the first major challenges for Starmer, whose center-left Labour Party took power last month in a landslide election victory, ousting the Conservative Party after 14 years. 

While the U.K. is one of the richest nations in the world, it faces a cost-of-living crisis, and its public health service is struggling to meet demand. And despite being the world’s sixth-largest economy, it has the highest levels of child poverty among richest countries, according to UNICEF.

While the Labour Party was successful in the general election, at least part of its success was due to a far right galvanized by a surge in support, which split the right-wing vote, causing many Conservative lawmakers to lose their seats in Parliament.