What are threat levels?

The system of threat levels has been created to keep you informed about the level of threat the UK faces from terrorism at any given time.

This system helps police and other law enforcement agencies decide how to allocate staff. The threat level represents the likelihood of an attack in the near future. More about the UK threat level system (Opens in a new window) on the MI5 website.

The five levels are:

• critical – an attack is expected imminently
• severe – an attack is highly likely
• substantial – an attack is a strong possibility
• moderate – an attack is possible but not likely
• low – an attack is unlikely