MI5 Chief Warns of Rising Iranian and Russian Threats to the U.K.

MI5 chief Ken McCallum warned that the U.K. faces a sharp rise in threats from hostile states, including Russia and Iran. In an October 16, 2025 address, he said the number of people MI5 investigates for state-threat activity had risen by 35% in a year. He also disclosed that the agency had tracked more than 20 potentially lethal Iran-backed plots during the past 12 months. McCallum said Russia recruits online proxies for hostile activity, while Iran seeks to silence opponents abroad