UK threat levels - wikipedia UK threat levels British military personnel guarding Downing Street as part of Operation Temperer following the 2017 Manchester Arena bombing. The United Kingdom Terror Threat Levels, often referred to as UK Threat Levels, are the alert states that have been in use since 1 August 2006 by the British government to warn of forms of terrorist activity. Before then a colour - based alert scheme known as BIKINI state was used. The response indicates how government departments and agencies and their staffs should react to each threat level. Contents 1 Current threat level 2 Categories of threat 3 Threat levels 4 History 5 Changes to threat levels 6 See also 7 References 8 External links Current threat level The current level was reduced to Severe on the afternoon of 17 September 2017 / It had been raised to Critical following the 2017 Parsons Green bombing on 15 September. The previous threat level to that was Severe having been reduced to that level following an increase to Critical after the Manchester Arena bombing of 22 May 2017. Categories of threat Since 24 September 2010, the Home Office has reported three different categories of terrorist threat : Threat from international terrorism. Terrorism threat related to Northern Ireland in Northern Ireland itself. Terrorism threat related to Northern Ireland in Great Britain ( i.e. excluding Northern Ireland ). A fourth category of terrorist threat is also assessed but is not disclosed, relating to threats to sectors of the UK 's Critical National Infrastructure such as the London Underground, National Rail network and power stations. The Joint Terrorism Analysis Centre ( JTAC ) is responsible for setting the threat level from international terrorism and the Security Service ( MI5 ) is responsible for setting both threat levels related to Northern Ireland. The threat level informs decisions on protective security measures taken by public bodies, the police and the transport sector. Threat levels Threat level Response Critical An attack is expected imminently. EXCEPTIONAL Maximum protective security measures to meet specific threats and to minimise vulnerability and risk. Critical may also be used if a nuclear attack is expected. Severe An attack is highly likely. HEIGHTENED Additional and sustainable protective security measures reflecting the broad nature of the threat combined with specific business and geographical vulnerabilities and judgements on acceptable risk. Substantial An attack is a strong possibility. Moderate An attack is possible, but not likely. NORMAL Routine protective security measures appropriate to the business concerned. Low An attack is very unlikely. History Wikinews has news related to : UK Threat Levels Threat levels were originally produced by MI5 's Counter-Terrorism Analysis Centre for internal use within the British government. Assessments known as Security Service Threat Reports or Security Service Reports were issued to assess the level of threat to British interests in a given country or region. They had six levels : Imminent, High, Significant, Moderate, Low and Negligible. Following terrorist attacks in Indonesia in 2002, the system was criticised by the Intelligence and Security Committee of Parliament ( ISC ) as insufficiently clear and needing to be of greater use to `` customer departments ''. The 7 July 2005 London bombings prompted the government to update the threat level system following a recommendation from the ISC that it should deliver `` a greater transparency of the threat level and alert systems as a whole, and in particular ( it is recommended ) that more thought is given to what is put in the public domain about the level of threat and required level of alert. '' The system was accordingly simplified and made easier to understand. Since 2006, MI5 and the Home Office have published international terrorism threat levels for the entire UK on their websites, and since 2010 they have also published threat levels for Northern Ireland, with separate threat levels for Northern Ireland and the rest of the UK. Changes to threat levels Graph showing the changes in threat levels between 2006 and today The following table records changes to the threat levels since August 2006 : Date National Threat Level Dates International terrorism Northern Ireland related terrorism 1 August 2006 Severe 24 September 2010 - 11 July 2011 Severe GB : substantial NI : severe 10 August 2006 Critical 11 July 2011 -- 23 October 2012 Substantial GB : substantial NI : severe 13 August 2006 Severe 24 October 2012 -- 29 August 2014 Substantial GB : moderate NI : severe 30 June 2007 Critical 29 August 2014 -- 10 May 2016 Severe GB : moderate NI : severe 4 July 2007 Severe 11 May 2016 -- 22 May 2017 Severe GB : substantial NI : severe 20 July 2009 Substantial 23 May 2017 -- 26 May 2017 Critical GB : substantial NI : severe 22 January 2010 Severe 27 May 2017 -- 15 September 2017 Severe GB : substantial NI : severe 11 July 2011 Substantial 15 September 2017 - 17 September 2017 Critical GB : substantial NI : severe 29 August 2014 Severe 17 September 2017 - current Severe GB : substantial NI : severe 23 May 2017 Critical 27 May 2017 Severe 15 September 2017 Critical 17 September 2017 Severe Jump up ^ Threat level increased following the 2006 transatlantic aircraft plot. Jump up ^ Threat level increased following the 2007 Glasgow Airport attack. Jump up ^ Threat level increased following the 2017 Manchester Arena attack. Jump up ^ Threat level increased following the 2017 Parsons Green bombing. See also Operation Temperer Terrorism in the United Kingdom DEFCON References Jump up ^ Threat Levels, July 2006 Jump up ^ `` Terror threat lowered after Tube bombing ''. BBC News. 2017 - 09 - 17. Retrieved 2017 - 09 - 22. Jump up ^ `` Parsons Green : UK terror threat increased to critical after Tube bomb ''. BBC News. UK. 2017 - 09 - 15. Retrieved 2017 - 09 - 15. Jump up ^ Dodd, Vikram ; Halliday, Josh ; Pidd, Helen ; agencies ( 2017 - 05 - 27 ). `` Manchester attack : UK terror threat level reduced to severe ''. The Guardian. ISSN 0261 - 3077. Retrieved 2017 - 09 - 22. Jump up ^ `` UK threat level raised to highest level ''. BBC News. 2017 - 05 - 23. Retrieved 2017 - 05 - 23. Jump up ^ `` Irish terror attack a ' strong possibility ' ''. BBC News. 25 September 2010. Retrieved 20 December 2010. Jump up ^ `` Press Release : Increased risk of Irish - related terrorism ''. United Kingdom Home Office. 24 September 2010. Retrieved 20 December 2010. Jump up ^ Bunkall, Alistair ( 4 June 2016 ). `` Was it a mistake to lower the UK terror threat before London Bridge attack ? ''. Sky News. Retrieved 4 June 2016. ^ Jump up to : `` Threat levels ''. MI5. Retrieved 1 April 2017. Jump up ^ Foley, Frank ( 2013 ). Countering Terrorism in Britain and France : Institutions, Norms and the Shadow of the Past. Cambridge University Press. p. 166. ISBN 978 - 1 - 107 - 02969 - 9. Jump up ^ Hennessey, Thomas ; Thomas, Claire ( 2011 ). Spooks the Unofficial History of MI5 From the First Atom Spy to 7 / 7 1945 - 2009. Amberley Publishing Limited. pp. 228 -- 9. ISBN 978 - 1 - 4456 - 0801 - 3. Jump up ^ Staniforth, Andrew ; Sampson, Fraser ( 2012 ). The Routledge Companion to UK Counter-Terrorism. Routledge. p. 276. ISBN 978 - 1 - 136 - 25430 - 7. Jump up ^ `` UK terror threat level raised to critical, meaning an attack is imminent, Prime Minister says ' ''. The Telegraph. 15 September 2017. Retrieved 15 September 2017. External links Current Threat Level, Home Office Threat Levels history from 1 August 2006, MI5 Retrieved from `` https://en.wikipedia.org/w/index.php?title=UK_Threat_Levels&oldid=801859875 '' Categories : 2006 introductions Alert measurement systems Counter-terrorism in the United Kingdom Emergency management in the United Kingdom Hidden categories : EngvarB from March 2017 Use dmy dates from March 2017 Talk Contents About Wikipedia Add links This page was last edited on 22 September 2017, at 10 : 42. About Wikipedia

Question: what level of terror alert is the uk at
Answer: Severe