--- description: Britain raised its national security threat level to critical from severe, meaning an attack is expected in the wake of a bomb in London title: The U.K. Just Raised the Terror Level to Critical image: https://static.time.com/v3/assets/bltea6093859af6183b/blta58fb83f869abd51/6988de07e76ad27b4462f2c3/london-attack-security-level-critical.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 ---  * [World](/section/world/) ## World Update your preferences in [Account Settings](/account/preferences/) Close * [United Kingdom](/tag/united-kingdom/) ## United Kingdom Update your preferences in [Account Settings](/account/preferences/) Close # U.K. Officials Just Raised the Terror Level to Critical. It Means They Expect Another Attack by [Kate Holton and William Schomberg / Reuters](/author/reuters/) ## Kate Holton and William Schomberg / Reuters Update your preferences in [Account Settings](/account/preferences/) Close Sep 15, 2017 7:56 PM CUT  An armed police officer stands nearby after an incident on a tube train at Parsons Green subway station in London, Friday, Sept. 15, 2017. An armed police officer stands nearby after an incident on a tube train at Parsons Green subway station in London, Friday, Sept. 15, 2017.Frank Augstein—AP by [Kate Holton and William Schomberg / Reuters](/author/reuters/) ## Kate Holton and William Schomberg / Reuters Update your preferences in [Account Settings](/account/preferences/) Close Sep 15, 2017 7:56 PM CUT (LONDON) – Britain lifted its national security threat level to critical from severe on Friday, meaning an attack is expected, after a bomb on a London commuter train injured 29 people. Prime Minister Theresa May said in a televised statement that armed police and members of the military would be seen on the streets in the coming days. “For this period, military personnel will replace police officers on guard duties at certain protected sites that are not accessible to the public,” she said. ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/4944313/london-terror-attack-security-critical/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/4944313/london-terror-attack-security-critical/"},"headline":"U.K. Officials Just Raised the Terror Level to Critical. It Means They Expect Another Attack","datePublished":"2017-09-15T19:56:09.000Z","dateModified":"2026-02-23T17:27:15.830Z","description":"Britain raised its national security threat level to critical from severe, meaning an attack is expected in the wake of a bomb in London","url":"https://time.com/4944313/london-terror-attack-security-critical/","keywords":["United Kingdom","onetime"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/blta58fb83f869abd51/6988de07e76ad27b4462f2c3/london-attack-security-level-critical.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Kate Holton and William Schomberg / Reuters"}],"articleSection":"World","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/blta58fb83f869abd51/6988de07e76ad27b4462f2c3/london-attack-security-level-critical.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"Britain Subway Incident","caption":"Britain Subway Incident","creditText":"Frank Augstein—AP","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/world/","name":"World"}},{"@type":"ListItem","position":2,"item":{"@id":"/tag/united-kingdom/","name":"United Kingdom"}},{"@type":"ListItem","position":3,"item":{"@id":"https://time.com/4944313/london-terror-attack-security-critical/","name":"U.K. Officials Just Raised the Terror Level to Critical. It Means They Expect Another Attack"}}]}] ```