UK Threat Level from International Terrorism 2006-2018
Transatlantic aircraft (liquid bomb) plot
10 August 2006
Glasgow Airport attack
30 June 2007
Manchester Arena attack
23 May 2017
Parsons Green attack
15 Sept 2017
2006Interact with the graphic to find out more about the events that caused the threat level to become CRITICAL.2017
Northern Ireland-related terrorism (NIRT)
Extreme Right Wing
UK Attack Methodology scale
The Joint Terrorism Analysis Centre (JTAC) assesses that the threat from international terrorism to the United Kingdom (UK) is SEVERE, meaning an attack is highly likely. MI5 assesses that the threat from Northern Ireland-related terrorism to Great Britain is MODERATE, meaning an attack is possible, but unlikely.
Last year the UK threat level was twice raised to CRITICAL, meaning an attack was imminent. This represents 46% of the time the country has spent at CRITICAL since the threat levels were made public in 2006.
Deputy Head of Risk Analysis
Islamist extremists are the principal threat to the UK. Daesh and AQ associates remain the key threat actors and likely targets are police, military and Government personnel and crowded places associated with iconic sites and the transport sector. Crowded places represent an opportunity for causing mass casualties, and the transport sector is a favoured target amongst Islamist extremists. Civil aviation remains a desired target, with the 2015 bombing of Metrojet Flight 9268 from Sharm el Sheikh triggering a new wave of aviation themed plots, reminding the Western world that security protocols were not infallible.
There were four successful Islamist extremist attacks in 2017 in the UK and the investigation into those attacks and the numerous disrupted plots are likely to have impacted upon the capabilities of both lone actors and extremist networks in the UK. Additionally, the attacks are likely to have reduced the threshold for risk the CT police and MI5 have in counter terrorism investigations. As such, it is probable that plots will be disrupted in far more immature stages which are likely to result in convictions for offences which carry a shorter custodial sentence. This shortened cycle of conviction, custodial sentence and release of terrorist prisoners is likely to compound the domestic terrorist threat. The severity of the UK threat is unlikely to reduce over the next two years. The latest official statistics1 on terrorism arrests in 2018 show a 22% reduction on 2017; this may be accredited to the large number of arrests made in response to the Manchester and London attacks which accounted for a significant number of the 2017 arrests. With that in mind, 351 arrests for terrorism-related activity is still comparatively high and Islamist extremism accounts for both the majority of the arrests and 82% of the total terrorism prison population.
It is probable that plots will be disrupted in far more immature stages which are likely to result in convictions for offences which carry a shorter custodial sentence.
Northern Ireland related terrorism (NIRT)
In March 2018 MI5 reduced the threat level from NIRT to Great Britain to MODERATE, meaning an attack was possible, but unlikely. This indicates that whilst some degree of hostile intent may remain within dissident republicans to attack the mainland, they currently lack the capability to do so or there has been an absence of active attack plans. The case of Ciaran Maxwell, the former Royal Marine convicted of terrorism offences and his suspected affiliations with the Continuity IRA (CIRA) appear an isolated incident although a stark reminder of both the military grade weapons which dissident republicans have available and how police, military and Government personnel are the likely focus of any attention. NIRT remains extremely active in Northern Ireland, with attacks highly likely and the New IRA representing the most significant threat.
Extreme Right Wing
The threat from XRW groups to the UK is growing. In 2017 there was one XRW attack, targeting people leaving Finsbury Park Mosque, and since March that year there have been at least four disrupted XRW attack plots, accounting for around 24% of disrupted plots in the UK. Arrests and custodial sentences for XRW activity in the UK have also steadily increased over the past three years. Latest official statistics state 13% of terrorist prisoners hold XRW ideologies, representing 28 people and an increase from 10 people in the previous year.
The greatest XRW threat to the UK is the proscribed organisation National Action, described by Assistant Commissioner of Specialist Operations Neil Basu QPM as the first XRW group to represent a national security threat. The presence of many serving military personnel within National Action compounds the threat they pose, given their training and access to firearms and explosives, all of which indicate the severity of such attacks may increase.
Islamist extremist attacks are highly likely to continue and, considering the diminished role of the so-called Caliphate in Iraq and Syria and disrupted communications from senior leaders there, attackers within the UK are less likely to have received specific instructions from overseas. Attackers are more likely to be inspired by a general Islamist extremist rhetoric. Likely targets are police, military and Government personnel and sites, along with crowded places associated with iconic sites and transport. XRW activity is likely to continue and probably increase, and violence directed towards the Muslim community using vehicles and military grade weapons cannot be ruled out.
UK Attack Methodology scale
The methodology of attacks may be wide ranging, with low complexity attacks using knives and vehicles as weapons being the most probable. The use of improvised explosive devices is likely to continue, particularly those incorporating TATP (Triacetone Triperoxide) above any other homemade explosives. The acquisition and use of firearms cannot be ruled out and remains a significant risk.