Keir Starmer warned social media companies that crimes were taking place “on your premises” after violent disorder across Britain by far-right demonstrators this week appeared to be sparked by online misinformation.

“Let me say to large social media companies: violent disorder, clearly whipped up online, that is also a crime and it’s happening on your premises,” the prime minister said at a press conference in Downing Street on Thursday.

Starmer was speaking following a riot on Tuesday by far-right demonstrators in Southport, a town in north-west England where three young girls were killed and eight other children were stabbed on Monday. Further disorder took place across the country on Wednesday evening, with police arresting 111 people in London.

The demonstration in the capital - which had been promoted on the social media platform X by the account of far-right agitator Stephen Yaxley-Lennon, better known as Tommy Robinson - took place on Whitehall and in Parliament Square, close to Starmer’s Downing Street residence. Videos posted on X showed protesters calling the police “traitors” and chanting “shame on you,” “save our kids” and “rule Britannia.”

“There is a balance to be struck,” Starmer said, praising the benefits of social media but warning: “There is a responsibility that goes with it.”

“Inciting violence online is a criminal offence and that is not a matter of free speech,” the premier added.

In the hours after the stabbings, a number of influential right-wing accounts on X spread false information about the attacker, including claims that he was an asylum seeker or a refugee. In fact, the 17 year-old charged with murder and attempted murder over the attack was born in Cardiff, Wales, police said.

Others online incorrectly cited a Muslim name in connection with the killings, attributing the news to Channel 3 Now, a fake news organisation whose origins cannot easily be traced. A mosque was targeted by the far-right in Southport on Monday night.

“It’s not protest, it’s not legitimate, it’s crime, violent disorder,” Starmer said, vowing: “We will put a stop to it.”

The premier said he wanted rioters to be treated like football hooligans, telling reporters he had convened a meeting of police chiefs to coordinate a national response to the disorder.

“These thugs are mobile; they move from community to community and we must have a policing response that can do the same,” Starmer said. “Shared intelligence, wider deployment of facial recognition technology and preventive action: criminal behaviour orders to restrict their movements before they can even board a train, in just the same way we do with football hooligans.”

He indicated that having met with police leaders on Thursday, he’d take a similar approach with social media companies, contrasting that to “the performative politics of a government blaming everybody else.”

“My approach is different, which is to roll my sleeves up, get the relevant people around the table and fix the problems and meet the challenges that we have as a country,” he said. “We did that with law enforcement and the police this afternoon: a similar approach with social media.”

Disorder was also reported late Wednesday in Hartlepool, northeast England - where at least eight people were arrested - as well as in Aldershot, southern England, and in Manchester.

  - Bloomberg