MI5 Chief Warns Iran and Russia Are Escalating Hybrid Campaigns in Britain

MI5 Director General Sir Ken McCallum warned on October 13, 2026, that Britain faces a growing threat from hostile states. He said MI5’s state-threat caseload has quadrupled over the past decade and that the agency is devoting more resources to countering these risks than during the Cold War. McCallum described Russia as the leading state aggressor and said Iran is expanding its campaign in Britain, including activity targeting Jewish communities and military sites. He urged the public to help strengthen national resilience.