MI5 chief warns AI could widen terrorists’ access to biological weapons

• McCallum said AI could make dangerous biological knowledge easier for would-be attackers to obtain.
• He also warned AI might help create new pathogens.
• MI5 says terrorists have struggled to achieve chemical or biological capabilities.
• A new assessment centre based at MI5 will advise government departments on AI-related security threats.

MI5 director-general Ken McCallum warned that artificial intelligence could make biological weapons more accessible to terrorists. He said AI might give would-be attackers access to dangerous biological knowledge or help create previously unseen pathogens. ¹²

Terrorists have long sought chemical or biological capabilities, McCallum said, but achieving them has proved difficult. The warning came in his annual threat update at MI5’s London headquarters on 13 October. ²³

McCallum said MI5 had encountered terrorists seeking to use AI to improve reconnaissance and attack methods, including through AI-enabled drones. ¹⁴

MI5 has launched an AI Threat Assessment Centre, based within the service, to assess the national-security implications of AI. It brings together expertise from MI5 and other bodies, including the AI Security Institute, the National Crime Agency and the National Cyber Security Centre. The centre says it will produce assessments for government departments. ¹⁵

Footnotes

1. https://www.mi5.gov.uk/mi5-director-general-delivers-annual-threat-update?adhoc_referrer=011810075148 ↩ ↩² ↩³

2. https://www.independent.co.uk/news/uk/home-news/mi5-ai-uk-national-security-russia-iran-ken-mccallum-b3065898.html ↩ ↩²

3. https://apnews.com/article/mi5-uk-us-iran-mccallum-raf-fairford-a8a03a2dbac09648fa4c56f728fa09ac ↩

4. https://www.itv.com/news/2026-10-13/ai-could-give-terrorists-access-to-bioweapons-if-guardrails-fail-spy-chief-says ↩

5. https://www.mi5.gov.uk/about-us/ai-threat-assessment-centre?adhoc_referrer=061601001098 ↩