What is a Self-Initiated Terrorist (S-IT)?
A S-IT is defined as “Person(s) who threaten or mobilise to violence (as defined in Section 1 of the Terrorism Act 2000) without material support or personal direction from a terrorist organisation; but who may still be influenced or encouraged by the rhetoric or ideology of a group”. S-ITs have previously been referred to as ‘lone actors’.
What is the threat from S-ITs?
S-ITs continue to pose the most significant terrorist threat to the United Kingdom. They will highly likely employ a low-sophistication methodology like a bladed weapon.
S-ITs can emerge from any ideology, including Islamist, Extreme Right Wing (ERW) or Left Wing, Anarchist or Single Issue (LASI). They are also unpredictable and difficult to detect.
Some successful S-ITs have previously had contact with authorities such as the Police, Prevent, Prison and Probation services or Mental Health services.
Methodologies and targets
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A low-complexity attack and low-sophistication methodology is most likely in the UK, irrespective of ideology. This could include using bladed weapons such as knives. |
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Publicly accessible locations and religious institutions are the most likely targets for a S-IT attack. Some S-ITs are also likely to view authority figures as legitimate targets, such as the Police or representatives of government. |
S-IT radicalisation
Access to extremist material online is one of the key drivers for S-IT self-radicalisation. It is easily accessed by individuals, irrelevant of their ideology. There is a range of terrorist literature, across numerous ideologies, which encourages S-IT attacks.
Supporters of terrorist groups continue to leverage armed conflicts overseas for propaganda aimed at inspiring S-IT attacks in the West including the UK.
Mental health and S-ITs
The relationship between S-IT and various vulnerability factors (including, but not limited to, poor mental health and/or neurodivergence) is complex. For example, it is likely that poor mental health, if left untreated and combined with other detrimental human factors and circumstances, can make an individual more vulnerable to radicalisation. Studies have found that S-ITs display higher rates of mental health disorders compared to group based terrorists.
What does this mean for UK Businesses and the public?
By their very nature, attacks by S-ITs are difficult to detect. Nevertheless, as with all types of terrorist attacks, the public and business community have a vital role in alerting the authorities to suspicious activity that may be the prelude to a terrorist attack. This can include:
- Suspicious purchases of items or materials that could be used as a weapon or facilitate an attack
- Unusual, furtive or otherwise suspicious behaviour in a public place
- Unusual attention being paid to a particular venue or person
S-ITs can act alone, but are rarely truly alone. They are part of society, with neighbours, colleagues, case workers, family members and even friends. Someone will likely know of their intentions, beliefs, grievances or extremist ideology. The best chance to divert a S-IT from violence is for a bystander to trust their instincts and speak to police about their concerns.
Those with concerns around an individual should call the Anti-Terrorism Hotline on 0800 789 321 (or in an emergency 999).
Probability and Likelihood in Intelligence assessments
When describing threats in intelligence assessments, Counter Terrorism Policing utilises the Probabilistic Yardstick.
The Probabilistic Yardstick is a tool created by the Professional Head of Intelligence Analysis (PHIA), in the UK government, to standardise the way in which we describe probability in intelligence assessments. For example, if we use the term ‘likely’ what we mean is ‘a 55-75% chance’.
Use the scale below as a reference when reading ProtectUK Insights.
