In an interview featured in an upcoming book by The Independent's home affairs editor Lizzie Dearden, he added: "The ones who are going to go from passive supporters [of terrorism], doing nothing illegal, through to acting on it is a small number. Spotting that small number in those tens of thousands is the needle in a haystack."
The senior officer said the UK lacks "a strong national capability to counter extremism" that underpins terrorism, warning: "Whilst not every extremist becomes a terrorist, every terrorist has been an extremist."
Sir Mark gave the interview for Plotters: The UK Terrorists Who Failed before he took up his current post as Metropolitan Police commissioner in September. He was the head of UK Counter Terrorism Policing from 2014 to 2018 - a period that saw a wave of terror attacks leave dozens of people dead in London and Manchester.
Denne historien er fra March 20, 2023-utgaven av The Independent.
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Denne historien er fra March 20, 2023-utgaven av The Independent.
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Ten-man Forest earn draw in feisty battle at the Bridge
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