In an annual threat update delivered at MI5's London headquarters on Tuesday, Director General Ken McCallum said there had been a notable increase in cases where "extremist versions of anti-immigration and anti-Muslim grievance are tipping into terrorist intent," with planning focused on attacks against migrants and Muslims.
McCallum highlighted that young people are particularly drawn to extreme rightwing terrorism, noting that at one point this year his agency was "investigating a radicalised … 13-year-old in the UK." He recalled that a year ago, a 16-year-old from Inverclyde received a 10-year prison sentence for planning mass murder by firebombing a Muslim centre in Greenock.
The warning comes amid a series of aggressive anti-migrant protests held this autumn by the far-right Patriot Platform at Portsmouth and Dover. Racially and religiously motivated offences are running at record levels in the UK, according to recent data.
McCallum also addressed hostile activity by Iran, saying the country now has "ambitions to come at harder targets, like military sites," referring to the RAF Fairford airbase in Gloucestershire. Over the past year, MI5's counter-Iran operation has led to more than 50 arrests in the UK, with much of Tehran's aggression aimed at "British Jewish communities," including terrorist plots and arson attacks against synagogues, businesses, and ambulances.
On Russia, McCallum described the Kremlin as "aggressor number one," continuing to pursue assassination plots, explosive threats, and cyber-attacks that he said stop "not much short" of conventional warfare. He acknowledged that Moscow tried to interfere in the 2016 Brexit referendum through anti-EU coverage on RT and Sputnik and via troll social media accounts, but noted a "big difference between what may have been attempted and what actually resulted."
Finally, McCallum said he was "particularly focused" on the risk that hostile states or terrorists could use artificial intelligence to generate new, deadly bioweapons.