London, Aug 2 : UK Prime Minister Keir Starmer has condemned far-right demonstrators for the violent disorder seen in parts of the country after a deadly knife attack in Southport on Monday.

"It's not protest. It's not legitimate. It's a crime. Violent disorder. An assault on the rule of law and the execution of justice," he said during a press conference held at Downing Street on Thursday.

Three children died and multiple others were injured after the attack at a Taylor Swift-themed dance workshop in Southport, northwest England. A 17-year-old boy from Banks in Lancashire has been arrested on suspicion of murder and attempted murder, although the motivation behind the attack remains unclear.

Online misinformation about the teenager's identity, targeting immigrants and Muslims, is thought to have fueled the violent protests in Southport, Hartlepool, and London, Xinhua news agency reported.

Since the attack, far-right activists have held several violent protests, which saw a mosque in Southport being attacked, and a police car in Hartlepool set on fire. Meanwhile, around 100 people were arrested after flares and bricks were hurled at the gates of Downing Street on Wednesday.

"The far right are showing who they are, we have to show who we are in response to that," Starmer said, adding: "Mosques targeted because they're mosques, flares thrown at the statue of Winston Churchill, a Nazi salute at the Cenotaph."

The Prime Minister announced that a national unit will be established across police forces to tackle violent disorder.

"These thugs are mobile. They move from community to community. We must have a policing response that can do the same," he said.

Starmer also urged social media companies to take responsibility in the country's fight against misinformation and violence.

"Let me also say to large social media companies and those who run them: violent disorder, clearly whipped up online, is also a crime, it's happening on your premises, and the law must be upheld everywhere," he said.

/IANS