Keir Starmer has warned a cohort of extreme loners need to factored into UK security plans in the aftermath of the Southport murders.
The PM's comments after killer Axel Rudakubana was jailed for a minimum of 52 years for the murder of three young girls at a Taylor-Swift themed dance class.
Speaking on Tuesday, Mr Starmer said: "When it comes to extremism, it's very important that we are focused on the threats so we can deploy our resources properly and therefore we're looking carefully where the key challenges are.
"Obviously, that's now informed with what I said last week in the aftermath of the Southport murders, where we've got the additional challenge, I think, of a cohort of loners who are extreme and they need to be factored in.
"So that's the focus. In the end, what this comes down to is the safety and security of people across the United Kingdom, that's my number one focus."
Last week Mr Starmer said Rudakubana, 18, presented a new kind of threat, distinct from politically or ideologically motivated terrorism, with "acts of extreme violence perpetrated by loners, misfits, young men in their bedroom, accessing all manner of material online, desperate for notoriety".
Be the first with news from Mirror Politics
BLUESKY: Follow our Mirror Politics account on Bluesky here. And follow our Mirror Politics team here - Lizzy Buchan, Jason Beattie, Kevin Maguire, Sophie Huskisson, Dave Burke, Ashley Cowburn, Mikey Smith
POLITICS WHATSAPP: Be first to get the biggest bombshells and breaking news by joining our Politics WhatsApp group here. We also treat our community members to special offers, promotions, and adverts from us and our partners. If you want to leave our community, you can check out any time you like. If you’re curious, you can read our Privacy Notice.
NEWSLETTER: Or sign up here to the Mirror's Politics newsletter for all the best exclusives and opinions straight to your inbox.
PODCAST: And listen to our exciting new political podcast The Division Bell, hosted by the Mirror and the Express every Thursday.
The PM's comments today also follow the leak of a Home Office review suggesting the UK's approach to extremism should be based on concerning behaviours and activity rather than ideologies.
Those include spreading misinformation, influencing racism, and involvement in "an online subculture called the manosphere", according to the right-leaning think tank Policy Exchange.
But the Home Secretary Yvettee Cooper is expected to reject the advice of the "rapid analytical sprint on extremism" she commissioned in August following the riots sparked by the Southport murders.
A Home Office spokesman said: "The counter extremism sprint sought to comprehensively assess the challenge facing our country and lay the foundations for a new approach to tackling extremism - so we can stop people being drawn towards hateful ideologies.
"This includes tackling Islamism and Extreme Right Wing ideologies, which are the most prominent today. The findings from the sprint have not been formally agreed by ministers and we are considering a wide range of potential next steps arising from that work."