Russian spies plan ‘mayhem on British streets’, warns MI5 chief

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Russian spies are on a “mission to generate mayhem on British streets” while Iran has been fomenting lethal plots against the UK at “an unprecedented pace and scale”, the head of the British domestic intelligence service warned.

Instances of spying against the UK by other states rose by a half over the past year, MI5 head Ken McCallum said on Tuesday, while the range of threats that the UK now faced, including terrorism, were “the most complex and interconnected . . . we’ve ever seen”.

The number of aggressive state actions investigated by his agency had “shot up” by 48 per cent over the past year alone, he said, and MI5 had responded to 20 potentially lethal Iran backed plots since January 2022.

“MI5 has one hell of a job on its hands,” McCallum said in his annual threat assessment. Alongside its counterterrorism work, which has continued at a more or less steady level for the past five years, MI5 was also having to confront “state-backed assassination and sabotage plots, against the backdrop of a major European war”, he said.

McCallum said that MI5 had so far not seen the rising conflict in the Middle East lead directly to increased terrorism incidents in the UK.

“We are powerfully alive to the risk that events in the Middle East trigger terrorist action in the UK”, but “we haven’t — yet — seen this translate at scale into terrorist violence,” he said.

Nonetheless, radicalisation stemming from recent events in the Middle East was a “slow burn” process, McCallum cautioned, adding that established groups such as Islamic State and al-Qaeda had “resumed efforts to export terrorism”.

McCallum said the return of these groups was the “terrorist trend that concerns me most”. Over the past month more than a third of MI5’s highest priority investigations were linked to organised overseas terrorist groups.

Another disturbing development is that one in eight terrorists now being investigated in the UK are under 18 years old, he said.