What are the UK terror threat levels? Why terrorism level has been reduced, by who and what each stage means

There are five different levels in which the threat of terrorism is decided in the UK

UK’s terrorism threat level has been reduced from severe to substantial, meaning the chance of an attack occurring is now “likely”.

The threat level had been raised to “highly likely” in November 2021 following an explosion at Liverpool Women’s Hospital.

The explosion killed the passenger and injured the driver, who managed to lock the suspected terrorist inside the taxi and escape before the vehicle caught fire.

The driver, named locally as David Perry, has been heralded a hero.

Here’s what the UK terrorism threat levels mean.

What are the UK terrorism threat levels?

There are five different levels in which the threat of terrorism is decided.

The levels are designed to give a broad indication of the likelihood of a terrorist attack based on sensitive and confidential information.

The five UK terror threat levels are: low, moderate, substantial, severe and critical.

UK terror threat levels. (Graphic: Mark Hall / JPIMedia)

How are the UK terrorism threat levels decided?

The UK’s terrorism threat levels are decided independently from government ministers by the Joint Terrorism Analysis Centre (JTAC).

It judges the current threat of a terrorist attack and is used by police and other security practitioners to decide what protective operations may be required.

Decisions are based on several factors of national security, including available intelligence, terrorist capability, terrorist intentions and timescale of a likely attack.

What does the ‘substantial’ terrorism threat level mean?

A ‘severe’ terrorism threat level means an attack is highly likely, according to the MI5.

It is one up from ‘substantial’ and one below ‘critical’ in the security service’s five levels used to determine the threat of terrorism on the UK.

  • Low: means an attack is highly unlikely
  • Moderate: means an attack is possible but not likely
  • Substantial: means an attack is likely
  • Severe: means an attack is highly likely
  • Critical: means an attack is highly likely in the near future

How frequent does the threat level change?

The UK terror threat level changes in accordance to terrorism activity.

Prior to November 2021, the last time the UK terrorism threat level was ‘severe’ was November 2020. It was lowered to ‘substantial’ in February 2021.

Prior to that it had been ‘substantial’ - meaning an attack was likely - for almost a year, after the threat level was ‘severe’ from July 2019 to November 2019.

The UK’s national terrorism threat level is currently ‘substantial’.

Home secretary Priti Patel told MPs: “The decision to change the UK terrorism threat level is taken by JTAC independently of ministers.

“JTAC keep the threat level under constant review based on the very latest intelligence and analysis of internal and external factors which drive the threat.

“Any reduction in the threat level is positive but it must never make us complacent. Terrorism remains one of the most direct and immediate risks to our national security. The public should remain alert, but not alarmed, and report any concerns they may have to the police.”

The threat level of international terrorism had changed 23 times since it was first published in August 2006.

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