The head of the Security Service (MI5) Sir Ken McCallum has revealed that “children under 17” made up a fifth of terror suspects in 2024.
Sir Ken said that terrorism is bred in the “squalid corners of the internet” and the online world can blur people’s motives.
This makes if harder for the Security Service to make assessments as to what drives the attackers.
MI5 has a new Interventions Centre of Expertise to manage adolescents over any threats and where there is mental health issues or any other type of complex issues they may have.
Sir Ken said, “Sadly, we continue to see a concerning number of minors in our national security investigations: one in five of the 232 terrorism arrests last year were of children under 17.
“This needs fresh thinking.”
In a speech at the Security Service’s Thames House headquarters in London, he said: “Terrorism breeds in squalid corners of the internet where poisonous ideologies, of whatever sort, meet volatile, often chaotic individual lives.
“The online environment can blur motive, too. Some situations are clear-cut. But it’s often messier.
“In 2025, it can be hard to tell in the immediate aftermath of an appalling violent crime whether the incident is terrorist or state-directed, and thus a national security matter, or non-ideological, driven by a unique personal grievance, fixation or mental disturbance.
“We are particularly conscious of these complexities when it comes to vulnerable young people.”
The intervention unit is part of the Counter Terrorism Operations Centre and is made up of other agencies and public services.
Sir Ken said, “If a vulnerable young person on a pathway towards extremist violence can receive the right support, such that expensive and scarce MI5 capabilities are not needed and fewer children feature in national security prosecutions, that’s good for everyone involved.”
