LONDON (AP) —Police in the north of England town of Rotherham struggled to hold back a mob of far-right rioters who were seeking to break into a hotel housing asylum-seekers.

Before bringing the riot under some sort of control, police officers with shields had faced a barrage of missiles, including bits of wood, chairs and fire extinguishers, as they sought to prevent the rioters, many of whom wore masks, from entering the Holiday Inn Express hotel. A small fire in a wheelie bin was also visible while windows in the hotel were smashed.

READ MORE: UK government warns of tough response to far-right protests as police prepare for more unrest

A police helicopter circled overhead, and at least one injured officer in riot gear was carried away as the atmosphere turned increasingly febrile.

U.K. Prime Minister Keir Starmer condemned the attack, describing it as “far-right thuggery” as violence broke out in several towns and cities across the country.

In a statement from 10 Downing Street on Sunday afternoon, the prime minister vowed that “we will do whatever it takes to bring these thugs to justice” as he addressed the nation following ongoing unrest across parts of the country.

It was the latest bout of rioting to grip the U.K. following a stabbing rampage at a dance class last week in the north of England that left three girls dead and several wounded.

Oliver Coppard, the mayor of South Yorkshire of which Rotherham is part, said he was “utterly appalled” by the violence.

“What we’re seeing is not protest, it is brutal thuggery directed against some of the most vulnerable people in our society,” he said. “We will come after those carrying out this violence with the full force of the law.”

Elsewhere, the atmosphere is also particularly tense in the northeast town of Middlesborough, where some protesters broke free of a police guard.

One group walked through a residential area smashing the windows of houses and cars. When asked by a resident why they were breaking windows, one man replied, “Because we’re English.” Hundreds of others squared up to police with shields at the town’s cenotaph, throwing bricks, cans and pots at officers.

More demonstrations are taking place around the U.K., but mainly in England, with counter-demonstrators also set to make their presence felt.

On Saturday, far-right activists faced off with anti-racism protesters across the U.K., with violent scenes playing out in locations from Belfast, the capital of Northern Ireland, to Liverpool in the northwest of England and Bristol in the west. Police made about 100 arrests but more are likely as officers scour CCTV, social media and footage from body-worn cameras.

Police have warned that widespread security measures, with thousands of officers deployed, mean that other crimes may not be investigated fully.

“We’re seeing officers that are being pulled from day-to-day policing,” Tiffany Lynch from the Police Federation of England and Wales told the BBC. “But while that’s happening, the communities that are out there that are having incidents against them — victims of crime — unfortunately, their crimes are not being investigated.”

The violence that has engulfed the country over the past few days erupted in the wake of Monday’s stabbing attack in Southport. A 17-year-old male has been arrested.

False rumors spread online that the suspect 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. Rudakubana has been charged with three counts of murder, and 10 counts of attempted murder.

Police said many of the weekend actions were organized online by shadowy far-right groups, who mobilize support with phrases like “enough is enough,” “save our kids” and “stop the boats.” They are tapping into concerns about the scale of immigration in the country, in particular the tens of thousands of migrants arriving in small boats from France across the English Channel.

Calls for protests have come from a diffuse group of social media accounts, but a key player in amplifying them is Stephen Yaxley-Lennon, a longtime far-right agitator who uses the name Tommy Robinson. He led the English Defense League, which Merseyside Police has linked to the violent protest in Southport on Tuesday, a day after the stabbing attack.

The group first appeared around 2009, leading a series of protests against what it described as militant Islam that often devolved into violence. Yaxley-Lennon was banned from Twitter in 2018 but allowed back after it was bought by Elon Musk and rebranded as X. He has more than 800,000 followers.

The group’s membership and impact declined after a few years, and Yaxley-Lennon, 41, has faced myriad legal issues. He has been jailed for assault, contempt of court and mortgage fraud and currently faces an arrest warrant after leaving the U.K. last week before a scheduled hearing in contempt-of-court proceedings against him.

Nigel Farage, who was elected to parliament in July for the first time as leader of Reform U.K., has also been blamed by many for encouraging — indirectly — the anti-immigration sentiment that has been evident over the past few days. While condemning the violence, he has criticized the government for blaming it on “a few far-right thugs” and saying “the far right is a reaction to fear … shared by tens of millions of people.”

Starmer has blamed the violence on “far-right hatred” and vowed to end the mayhem. He said police across the U.K. would be given more resources to stop “a breakdown in law and order on our streets.”

Policing minister Diana Johnson told the BBC that there is “no need” to bring in the army to help police in their efforts to confront the violence.

Associated Press writer Jill Lawless contributed to this report.