British Prime Minister Keir Starmer has condemned an attack on a hotel housing asylum seekers, calling it “far-right thuggery” as widespread violence broke out.

Police in a northern England town have struggled to hold back a mob of far-right activists who were seeking to break into a hotel housing asylum seekers, as riots continued across parts of Britain.

At least 10 police officers were injured, including one left unconscious, after rioters tried to storm the Holiday Inn Express hotel in Rotherham on Sunday.

Anti-immigration demonstrators threw planks of wood at officers and sprayed them with fire extinguishers.

Hotel employees and residents, some of whom are asylum seekers, were terrified, but no injuries were reported, police said.

The unrest was sparked after a stabbing rampage at a dance class last week that left three girls dead and several wounded.

Starmer condemned the attack as violence also broke out in other towns and cities across the country.

“To those who feel targeted because of the colour of your skin or your faith, I know how frightening this must be,” he said.

“I want you to know that this violent mob do not represent our country, and we will bring them to justice.”

Mosques will be offered greater protection with new “emergency security” that can be rapidly deployed to respond to violent disorder sweeping across parts of England, the Home Office has announced.

More demonstrations are expected across Britain, with crowds of counter-demonstrators also set to make their presence felt.

On Saturday, far-right activists faced off with anti-racism protesters across the UK, with violent scenes playing out from Belfast, the capital of Northern Ireland, to Liverpool in the north-west of England and Bristol in the west.

Further arrests are likely as police scour CCTV, social media and body-worn camera footage.

In just one incident on Saturday, Merseyside Police said about 300 people were involved in violent disorder in Liverpool, in which a community facility was set on fire.

The Spellow Lane Library Hub, which was opened last year to provide support for one of Britain’s most deprived communities, suffered severe damage to the ground floor.

Police said rioters tried to prevent firefighters from getting to the fire, throwing an object at a fire engine and breaking its rear window.

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

“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 erupted earlier this week, ostensibly in protest of last week’s deadly stabbing attack in Southport. A 17-year-old male has been arrested and charged.

False rumours spread online that the young man was a Muslim and an immigrant, fuelling anger among far-right supporters.

Suspects under 18 are usually not named in the UK, but Judge Andrew Menary ordered Axeel Rudakubana, who was 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.

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

“The police have made it very clear that they have all the resources they need at the moment,” she said.

-with AAP