Terrorists could use AI to target UK with drones and bioweapons, MI5 chief warns
Terrorists could exploit artificial intelligence to target Britain with drones or biological weapons, the head of MI5 has warned.
Speaking after his annual speech at MI5 headquarters in London, Sir Ken McCallum said the UK had entered a “new era of national security” and the security service was directing more resources to keeping Britain safe now than in the Cold War, warning that essential services such as banking, flights, and healthcare were at risk of being disrupted by adversaries, including Iran and Russia.
He warned about the growing threat of AI provoking real fear that terrorists could use the technology for warfare, saying “we’ve caught terrorists seeking to exploit AI to improve their reconnaissance and attack methodologies”.
He said the possibility of AI-enabled drones added “a new twist” for bad actors and warned the greatest concern is “AI’s potential to change the stakes on existing or even new bioweapons”.
“These risks are real. The UK Intelligence Community – MI5, GCHQ, MI6 – is working closely with the UK’s globally respected AI security institute to take them on. Part of that means retaining the capability edge against those who mean the UK harm. As they seek to harness AI, we must stay ahead, so these powerful technologies bolster rather than undermine our shared security,” he said.
Putting the public on guard, Sir Ken warned: “We have again entered a new era of national security”.
He called for a “whole-of-society effort” to face threats to national infrastructure, warning that hacks could disable people’s banking services, drones could disrupt flights, and cyber-attacks on hospitals could impact health treatment.
The MI5 director general also said that the suspected terror plot against RAF Fairford in Gloucestershire, which prime minister Andy Burnham said was “almost certainly” directed by Iran’s Islamic Revolutionary Guard, was “not unique in the UK”, with Iranians seeking to expand their hybrid campaign against Britain this year.
In the past twelve months, MI5 investigations have led to more than 50 arrests in Iran-linked operations in the UK, and its state threats caseload has quadrupled in the past decade, he said.
Sir Ken added: “You might be surprised to know that in 2026, MI5 is devoting more resource to countering state threats than during the Cold War.”
He said that there have been dozens of arrests under the National Security Act in the three years since it came into force, with cases linked to Russia, Iran and China.
“Anyone tempted by apparently easy cash from shady overseas taskmasters might want to bear this in mind,” Sir Ken warned.
He said that Russia remains “aggressor number one”, with Russian military and intelligence services “once again escalating their attempts at hybrid warfare”, citing a cyber-attack on Polish energy infrastructure and an attempt to use a drone to blow up a cargo plane in Germany.
Sir Ken also called out Iranian use of “criminal proxies to try and intimidate oppositionists, Iranian media organisations and Israeli sites”.
