Increase coincides with proscription of Palestine Action last year which has led to thousands of arrests for allegedly supporting the protest group

Almost half of all terrorism arrests in Great Britain since the 9/11 attacks on the twin towers in 2001 have come in the past year, official data shows.

There have been 6,539 arrests for terror-related activity in Great Britain since the 2001 attacks and 3,021 of those arrests were in the year ending 31 March 2026, according to the Home Office.