The head of MI5 issues a rare public intervention, urging a “call to arms” for society to treat national security as a shared responsibility.

Sky News reports that the MI5 chief frames national security as a challenge that requires engagement beyond government and security agencies, presenting the message as an appeal to wider public participation. The coverage describes the intervention as unusual for the agency, which typically operates without frequent public-facing remarks.

Yahoo UK News carries the same headline topic, indicating agreement that MI5’s leader makes a public call for people to take national security seriously. However, the shared material provided here does not include additional specifics about timing, the venues for the remarks, or particular threats referenced by the MI5 head.