British counterterrorism officials have warned that technology and online platforms are increasingly being used by hostile states, extremist organisations and far-right groups to threaten the United Kingdom, making online security a growing challenge.
Speaking on Thursday, Vicki Evans, the Metropolitan Police's senior national coordinator for counterterrorism, said tackling online threats has become a "constant battle" and stressed that police cannot address the problem without stronger cooperation from technology companies.
While Islamist extremism continues to pose the biggest security threat, officials said risks linked to far-right extremism and hostile foreign states have risen sharply over the past five years.
Laurence Taylor, head of counterterrorism policing, said hostile state activity has become one of the fastest-growing security concerns facing Britain.
Evans said police have uncovered more than 20 Iran-linked plots in 2025, including alleged assassination attempts, kidnappings and other serious crimes targeting the UK. Authorities are also investigating whether arson attacks on Jewish sites earlier this year were connected to Iran.
She added that Russia has continued to organise surveillance operations across Britain, targeting individuals and institutions, seeking to identify people viewed as enemies by Moscow and recruit others to spread Russian narratives or carry out activities on its behalf.
Across Europe, Russia has reportedly recruited dozens of people through messaging platforms such as Telegram to carry out acts of vandalism and arson, including an attack on a London warehouse storing communications equipment intended for Ukraine.
Authorities said Dylan Earl, who led that plot, was recruited through Telegram by the Wagner Group, a mercenary organisation designated as a terrorist group by the UK government.
Evans also revealed that police have arrested teenagers as young as 15 in connection with proxy operations linked to hostile states. She warned that anyone could become a target, particularly through online platforms.
"This isn't something happening somewhere else," she said. "It's happening here—in our communities, workplaces and online spaces."
Taylor said Britain's national terrorism threat level was raised from "substantial" to "severe" in April, partly because cases involving far-right extremism have increased significantly.
He said police have seen a rise in online content promoting racism, misogyny and extreme homophobia, creating an environment where extremist views are becoming more common and less likely to be challenged.
As an example, Taylor referred to the case of 18-year-old Alina Burns, who was sentenced to nearly 20 years in prison in May after attacking a stranger with an axe. Police said the attack was motivated by far-right extremist beliefs.
Officials also expressed concern about the growing online radicalisation of children and teenagers.
Taylor said 22-year-old Alfie Coleman, who was sentenced on Wednesday to 13 and a half years in prison for attempting to buy a gun from an undercover MI5 officer, had been radicalised online from the age of 14.
Evans said extremist groups are deliberately creating online content that appeals to young people by combining propaganda with gaming footage, music and historical images. Some are encouraged to imitate violent acts seen in video games or compete in carrying out harmful activities online and offline.
She warned that some online groups encourage cybercrime, violent extremism, serious assaults, child sexual abuse and even terrorism.
Evans also raised concerns about the widespread availability of violent and graphic online content that, while legal, can distort young people's understanding of what is acceptable and make them more vulnerable to manipulation by extremist groups and hostile states.
Although the UK government has proposed banning social media use for children under 16, Evans said that measure alone would not be enough. She called for technology companies to take greater responsibility for limiting harmful content, noting that laws often struggle to keep pace with rapidly evolving online platforms.
She warned that young people can quickly become drawn into harmful online content, making early intervention essential.