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Violent disturbances have followed dance class stabbing

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Starmer says whipping up of violence online is criminal

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PM adds that misinformation could prejudice future trial

(Updates Thursday's story with misinformation example in

paragraph 13)

By Alistair Smout and Nick Vant

LONDON, Aug 1 (Reuters) - British Prime Minister Keir

Starmer warned social media companies that they must uphold laws

that prohibit the incitement of violence online after

misinformation around a fatal mass stabbing earlier in the week

sparked violent scenes.

A 17-year-old boy appeared in an English court on Thursday

charged with the murder of three young girls in a knife attack

at a summer dance class in Southport that has shocked the nation

and sparked two nights of violent protests.

The disturbances followed the rapid spread of false

information on social media that the suspect in the stabbings

was a radical Islamist migrant, with anti-immigrant protesters

descending on Southport from elsewhere, attacking police and

targeting a mosque.

Starmer said that the disturbances were not legitimate

protests, saying it was criminal disorder that was "clearly

driven by far-right hatred" before adding a warning to tech

companies.

"Let me also say to large social media companies, and those

who run them, violent disorder clearly whipped up online: that

is also a crime. It's happening on your premises, and the law

must be upheld everywhere," he said at a news conference, adding

there was a "balance to be struck" in handling such platforms.

"It's an amazing opportunity that we all enjoy... There is

also a responsibility that goes with it. That's a space for a

mature conversation to take place."

BLIZZARD OF FALSE INFORMATION

Campaign group Hope Not Hate said that the riot in Southport

on Tuesday followed a "blizzard of false information around the

attack, much of it circulated by far-right accounts online."

The 17-year-old suspect was not initially named due to rules

regarding children who are charged with crimes, before a judge

then ruled that media could name him as Axel Rudakubana. He

turns 18 next week and police have said he was born in Cardiff.

But a claim that the suspect was an asylum seeker or

immigrant has been viewed at least 15.7 million times across X,

Facebook, Instagram and other platforms, a Reuters analysis

showed.

A false claim that he was an undocumented migrant who

arrived in a small boat appeared on the website "Channel 3 Now",

who later apologised for publishing information that was

misleading and not accurate.

Internet personality Andrew Tate on Tuesday shared a picture

of a man he said was responsible for the attack with the caption

"straight off the boat", but the claim was also incorrect as it

was a picture of a 51-year-old man arrested for a separate

stabbing in Ireland last year.

Thousands of people online also falsely claimed another man

pictured with a knife in French media after an attack in Annecy

last June was the Southport suspect. The man, a Syrian refugee,

has been in pre-trial detention in France since then.

Separately, a Channel 4 analysis showed that 49% of traffic

on social media platform X referencing 'Southport Muslim' - in

reference to an unevidenced claim about the attacker's religion

- came from the United States, with 30% coming from Britain.

Police have said the incident was not being treated as

terror-related, and have urged people not to speculate on

details while the investigation continues.

Nigel Farage, leader of the right-wing Reform Party, on

Tuesday said he wondered "whether the truth is being withheld

from us" as he questioned why the incident wasn't being treated

as terror-related and asked if the suspect had been monitored by

security services.

After criticism from several people including Starmer's

deputy Angela Rayner, accusing Farage of stoking conspiracy

theories, Farage said he thought his "gentle questions" were

fair and reasonable while adding that the internet had at the

same time been awash with unfounded theories.

Starmer declined to be drawn into commenting on what Farage

had said, reiterating that his focus was on the families and

police officers impacted.

But Starmer warned that any misinformation that interfered

in the work of authorities could jeopardise attempts to hold a

fair trial.

"The price for a trial that is prejudiced is ultimately paid

by the victims and their families who are deprived of the

justice that they deserve," he said.