In the absence of specific intelligence, a judgement will need to be made about how close an attack might be to fruition. We know from past incidents that some attacks take years to plan, while others are put together more quickly.

The threat level expresses the likelihood of an attack in the near term. Using intelligence and publicly available information to examine the overall aims of the terrorists and the ways they may achieve them including what sort of targets they would consider attacking. This would also analyse the potential scale of the attack. An examination of what is known about the capabilities of the terrorists in question and the method they may use based on previous attacks or from intelligence. Intelligence is only ever likely to reveal part of the picture. More often, judgements about the threat will be based on a wide range of information, which is often fragmentary, including the level and nature of current terrorist activity, comparison with events in other countries and previous attacks. It is rare that specific threat information is available and can be relied upon. Threat Levels are decided using the following information: Low and moderate measures appropriate to the business concerned. Critical measures to meet specific threats and to minimise vulnerability and riskĪdditional and sustainable substantial and severe protective security measures reflecting the broad nature of the threat combined with specific business and geographical vulnerabilities and judgements on acceptable risk. Threat levels Threat level Īn attack is highly likely in the near future. The threat level informs decisions on protective security measures taken by public bodies, the police and the transport sector. 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. excluding Northern Ireland).Ī 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. Terrorism threat related to Northern Ireland in Great Britain (i.e.

Terrorism threat related to Northern Ireland in Northern Ireland itself.

Previously, since 24 September 2010, the Home Office has reported three different categories of terrorist threat:

Northern Ireland-related Threat Level to Northern Ireland.

Since 23 July 2019, the Home Office has reported two different categories of terrorist threat: It was lowered to this level on 22 March 2022 having been at 'Severe' since 2010. The current level of Northern Ireland-related Threat Level to Northern Ireland is 'Substantial'. It had been raised to 'severe' following the Liverpool Women's Hospital bombing on 14 November 2021. The current National Threat Level is 'substantial”, which was set on 9 February 2022.

5.1 Old-Format, Historical Threat Levels.

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