Recognising the terrorist threat

Updated 28 October 2016

There is a serious and sustained threat from both international and Irish-related terrorism to the UK and UK interests overseas.

1. Threat levels

You can check the current threat levels:-

The most significant terrorist threat comes from international terrorism. As a number of recent European attacks have showed, attacks may be mounted without warning.

Northern Ireland-related terrorism continues to pose a threat. Dissident republican terrorist groups (such as the Real IRA and the Continuity IRA) have rejected the 1998 Good Friday Agreement. They still aspire to mount attacks within the UK mainland and have conducted attacks within Northern Ireland.

2. STAY SAFE : Terrorist Firearms and Weapons Attacks

Firearms and Weapons attacks are rare in the UK. The ‘STAY SAFE’ principles tell you some simple actions to consider at an incident and the information that armed officers may need in the event of a weapons or firearm attack:-

2.1 RUN

  • Escape if you can
  • Consider the safest options
  • Is there a safe route? RUN if not HIDE
  • Can you get there without exposing yourself to greater danger?
  • Insist others leave with you
  • Leave belongings behind

2.2 HIDE

  • If you cannot RUN, HIDE
  • Find cover from gunfire
  • If you can see the attacker, they may be able to see you
  • Cover from view does not mean you are safe, bullets go through glass, brick, wood and metal
  • Find cover from gunfire e.g. substantial brickwork / heavy reinforced walls
  • Be aware of your exits
  • Try not to get trapped
  • Be quiet, silence your phone and turn off vibrate
  • Lock / barricade yourself in
  • Move away from the door

2.3 TELL

Call 999 - What do the police need to know? If you cannot speak or make a noise listen to the instructions given to you by the call taker

  • Location - Where are the suspects?
  • Direction - Where did you last see the suspects?
  • Descriptions – Describe the attacker, numbers, features, clothing, weapons etc.
  • Further information – Casualties, type of injury, building information, entrances, exits, hostages etc.
  • Stop other people entering the building if it is safe to do so


  • Follow officers instructions
  • Remain calm
  • Can you move to a safer area?
  • Avoid sudden movements that may be considered a threat
  • Keep your hands in view


  • Point guns at you
  • Treat you firmly
  • Question you
  • Be unable to distinguish you from the attacker
  • Officers will evacuate you when it is safe to do so

You must STAY SAFE

  • What are your plans if there were an incident?
  • What are the local plans? e.g. personal emergency evacuation plan

Further Advice

citizenAID is a simple, clear teaching aid for immediate actions and first aid for a stabbing, bomb incident or mass shooting. Building on Run, Hide Tell, this helps people understand what to do in the event of an attack.

3. Suspicious items - Guidance for the Public

  • Do not touch
  • Try and identify an owner in the immediate area
  • If you still think it’s suspicious, don’t feel embarrassed or think anybody else will report it
  • Report it to a member of staff, security, or if they are not available dial 999 (do not use your mobile phone in the immediate vicinity)
  • Move away to a safe distance - Even for a small item such as a briefcase move at least 100m away from the item starting from the centre and moving out

Remember - If you think it’s suspicious, SAY SOMETHING

4. Suspicious items - Guidance for Staff

When dealing with suspicious items apply the 4 C’s protocol:-

4.1 CONFIRM whether or not the item exhibits recognisably suspicious characteristics

The HOT protocol may be used to inform your judgement:-


  • Has the item been deliberately concealed or is it obviously hidden from view?

OBVIOUSLY suspicious?

  • Does it have wires, circuit boards, batteries, tape, liquids or putty-like substances visible?
  • Do you think the item poses an immediate threat to life?

TYPICAL Is the item typical of what you would expect to find in this location?

  • Most lost property is found in locations where people congregate. Ask if anyone has left the item

If the item is assessed to be unattended rather than suspicious, examine further before applying lost property procedures.
However, if H-O-T leads you to believe the item is suspicious, apply the 4Cs.

4.2 CLEAR the immediate area

  • Do not touch it
  • Take charge and move people away to a safe distance. Even for a small item such as a briefcase move at least 100m away from the item starting from the centre and moving out
  • Keep yourself and other people out of line of site of the item. It is a broad rule, but generally if you can not see the item then you are better protected from it
  • Think about what you can hide behind. Pick something substantial and keep away from glass such as windows and skylights
  • Cordon off the area

4.3 COMMUNICATE - Call 999

  • Inform your control room and/or supervisor
  • Do not use radios within 15 metres

4.4 CONTROL access to the cordoned area

  • Members of the public should not be able to approach the area until it is deemed safe
  • Try and keep eyewitnesses on hand so they can tell police what they saw

5. Bomb threat guidance

The vast majority of bomb threats are hoaxes designed to cause alarm and disruption. As well as the rare instances of valid bomb threats, terrorists may also make hoax bomb threat calls to intimidate the public, businesses and communities, to draw attention to their cause and to mislead police. While many bomb threats involve a person-to-person phone call, an increasing number are sent electronically using email or social media applications.

No matter how ridiculous or implausible the threat may seem, all such communications are a crime and should be reported to the police by dialling 999.

It is important that potential recipients - either victims or third-parties used to pass the message - have plans that include how the information is recorded, acted upon and passed to police.

5.1 The bomb threat message

Bomb threats containing accurate and precise information, and received well in advance of an actual attack, are rare occurrences. Precise motives for hoaxing are difficult to determine but may include revenge, extortion, a desire to impress, or a combination of these and other less understandable motives. The vast majority of cases are hoaxes and the intent is social engineering, to cause disruption, fear and/or inconvenience the victim.

5.2 Communication of the threat

A bomb threat can be communicated in a number of different ways. The threat is likely to be made in person over the telephone; however, it may also be a recorded message, communicated in written form, delivered face-to-face or, increasingly, sent by email or social media (e.g. Twitter or Instagram, etc.). A threat may be communicated via a third-party, i.e. a person or organisation unrelated to the intended victim and identified only to pass the message.

5.3 Immediate steps if you receive a bomb threat communication

Any member of staff with a direct telephone line, mobile phone, computer or tablet etc., could conceivably receive a bomb threat. Such staff should, therefore, understand the actions required of them as the potential first response to a threat message.

If you receive a telephone threat you should:-

  • stay calm and listen carefully
  • have immediate access to a checklist on key information that should be recorded (see bomb threat checklist - attached)
  • if practical, keep the caller talking and alert a colleague to dial 999
  • if displayed on your phone, note the number of the caller, otherwise, dial 1471 to obtain the number once the call has ended
  • if the threat is a recorded message write down as much detail as possible
  • If the threat is received via text message do not reply to, forward or delete the message. Note the number of the sender and follow police advice
  • know who to contact in your organisation upon receipt of the threat, e.g. building security/senior manager. They will need to make an assessment of the threat

If the threat is delivered face-to-face:-

  • try to remember as many distinguishing characteristics of the threat-maker as possible

If discovered in a written note, letter or as graffiti:-

  • treat as police evidence and stop other people touching the item

If the threat is received via email or social media application:-

  • do not reply to, forward or delete the message
  • note the sender’s email address or username/user ID for social media applications
  • preserve all web log files for your organisation to help the police investigation (as a guide, 7 days prior to the threat message and 48 hours after)

REMEMBER Dial 999 and follow police advice. Seek advice from the venue security/operations manager as soon as possible.

5.4 Assessing the credibility of bomb threats

Evaluating the credibility of a threat is a critical task, particularly if the attack being threatened is imminent. This is a tactic used to place additional pressure on decision makers. Police will assess the threat at the earliest opportunity. When specific intelligence is known to police, advice will be issued accordingly; however, in the absence of detailed information, it will be necessary to consider a number of factors:-

  • is the threat part of a series? If so, what has happened elsewhere or previously?
  • can the location of the claimed bomb(s) be known with precision? If so, is a bomb visible at the location identified?
  • considering the hoaxer’s desire to influence behaviour, is there any reason to believe their words?
  • if the threat is imprecise, could an external evacuation inadvertently move people closer to the hazard?
  • is a suspicious device visible?

5.5 Actions to consider

Responsibility for the initial decision making remains with the management of the location being threatened. Do not delay your decision making process waiting for the arrival of police. Police will assess the credibility of the threat at the earliest opportunity. All bomb threats should be reported to the police and their subsequent advice followed accordingly. It is essential that appropriate plans exist, they should be event and location specific. Venue options to manage the risk include:-

External evacuation

Leaving the venue will be appropriate when directed by police and/or it is reasonable to assume the threat is credible, and when evacuation will move people towards a safer location.

It is important to appoint people, familiar with evacuation points and assembly (rendezvous) points, to act as marshals and assist with this procedure. At least two assembly points should be identified in opposing directions, and at least 500 metres from the suspicious item, incident or location. Where possible the assembly point should not be a car park. You may wish to seek specialist advice, which can help to identify suitable assembly points and alternative options as part of your planning. It is essential that evacuation plans exist; they should be event and location specific. Evacuation procedures should also put adequate steps in place to ensure no one else enters the area once an evacuation has been initiated.

The police will establish cordons depending upon the size of an identified suspect device. Always follow police directions and avoid assembly close to a police cordon.

Internal or inwards evacuation (‘invacuation’)

There are occasions when it is safer to remain inside. Staying in your venue and moving people away from external windows/walls is relevant when it is known that a bomb is not within or immediately adjacent to your building.

If the suspect device is outside your venue, people may be exposed to greater danger if the evacuation route inadvertently takes them past the device. A safer alternative may be the use of internal protected spaces. This type of inwards evacuation needs significant pre-planning and may benefit from expert advice to help identify an internal safe area within your building. These locations should be in your plans.

If the location of the device threatened is unknown, evacuation represents a credible and justifiable course of action.

Decision not to evacuate or inwardly evacuate

This will be reasonable and proportionate if, after an evaluation by the relevant manager(s), the threat is deemed implausible (e.g. a deliberate hoax). In such circumstances police may provide additional advice and guidance relating to other risk management options. It may be considered desirable to ask staff familiar with the venue to check their immediate surroundings to identify anything out of place, see search considerations below.

Checking your venue for suspicious items - Search Considerations

Regular searches of your establishment, proportionate to the risks faced, will enhance a good security culture and reduce the risk of a suspicious item being placed or remaining unnoticed for long periods. Additionally, if you receive a bomb threat and depending upon how credible it is, you may decide to conduct a ‘search’ for suspicious items. To that end:-

  • ensure plans are in place to carry out an effective search in response to a bomb threat
  • identify who in your venue will coordinate and take responsibility for conducting searches
  • initiate a search by messaging over a public address system (coded messages avoid unnecessary disruption and alarm), by text message, personal radio or by telephone cascade
  • divide your venue into areas of a manageable size for 1 or 2 searchers. Ideally staff should follow a search plan and search in pairs to ensure nothing is missed
  • ensure those conducting searches are familiar with their areas of responsibility. Those who regularly work in an area are best placed to spot unusual or suspicious items
  • focus on areas that are open to the public; enclosed areas (e.g. cloakrooms, stairs, corridors, lifts etc.) evacuation routes and assembly points, car parks, other external areas such as goods or loading bays
  • develop appropriate techniques for staff to be able to routinely search public areas without alarming any visitors or customers present
  • under no circumstances should any suspicious item be touched or moved in any way. Immediately start evacuation and dial 999
  • ensure all visitors know who to report a suspicious item to and have the confidence to report suspicious behaviour

Remember: it is vital that regular drills are carried out to ensure all are familiar with bomb threat procedures, routes and rendezvous points. Disabled staff should have personal evacuation plans and be individually briefed on their evacuation procedures. Similarly all visitors should be briefed on evacuation procedures and quickly identified and assisted in the event of a threat.

Familiarising through testing and exercising will increase the likelihood of an effective response to an evacuation and aid the decision making process when not to evacuate/invacuate.

5.6 Media and Communication

Avoid revealing details about specific incidents to the media or through social media without prior consultation with police. Do not provide details of the threat, the decision making process relating to evacuation (internal or external) or why a decision not to evacuate was taken.

Releasing details of the circumstances may:-

  • be an objective of the hoaxer and provide them with a perceived credibility
  • cause unnecessary alarm to others
  • be used by those planning to target other venues
  • elicit copycat incidents
  • adversely affect the subsequent police investigation

6. Vehicle-borne improvised explosive devices (VBIED)

VBIEDs can be highly destructive. Not only can the bomb blast be lethal, but flying debris, such as glass, can present a hazard.

VBIEDs can carry a large quantity of explosives to a target and cause a great deal of damage. The device can be delivered at a time of the terrorist’s choosing, with reasonable precision (depending on defences). It can be detonated from a safe distance using a timer or remote control, or can be detonated on the spot by a suicide bomber.

The UK has a history of VBIED-based terrorist attacks which used fertiliser-based explosives dating back to the early 1970s. In 1998 in Omagh a device containing agricultural fertiliser (ammonium nitrates) was detonated, killing 29 people and injuring hundreds. In 1996 in Manchester, a device made from a mixture containing agricultural fertiliser devastated the city.

Find out more about how to store hazardous materials safely and how to Secure your fertiliser.

6.1 Planning

Vehicle access controls

Use robust physical barriers to keep all but authorised vehicles at a safe distance. You should ensure you have effective controls, particularly at goods entrances and service yards:

  • do not allow unchecked vehicles to park in underground car parks or service areas directly below public areas or where there is a risk of structural collapse
  • demand that details be provided in advance for any contract vehicles and the identity of the driver and passengers coming to your goods or service areas.
  • deny access to any vehicle that arrives without prior notice.

Ask your local CTSA for advice on further measures, such as electronic surveillance (for example, automatic number plate recognition software) or options for protection from flying glass.

Physical security

Do what you can to make your premises blast resistant - paying particular attention to windows. You could have the structure checked by a qualified security or structural engineer.

You will need to balance the installation of physical barriers (for example, bollards) against safety requirements. Check your fire safety risk assessment and the planning regulations.

Personnel security

Organise and rehearse bomb threat and evacuation drills. In a VBIED incident, windowless corridors or basements may be safer than outside assembly points.

Train and rehearse staff in identifying suspect vehicles, and in receiving and acting upon bomb threats. Key information and telephone numbers should be prominently displayed and readily available.

The CPNI provides advice on hostile vehicle mitigation and has published Integrated Security: a public realm guide for hostile vehicle mitigation.

7. Suicide attacks

Suicide bombing is a very effective method of delivering an explosive device to a specific location. Suicide bombers may use a vehicle as a bomb or may carry or conceal explosives on themselves. The most likely targets are symbolic locations, key installations, VIPs or crowded places.

Explosions using homemade explosive devices have caused fatalities, injuries, and damage on a massive scale. The suicide bombers in the 2005 London attacks used precursor chemicals (in particular peroxide-based explosives) and killed 52 people and injured hundreds, many severely.

7.1 Planning

When planning protective measures for your site, you should consider:-

  • placing your vehicle access control point at a distance from the site
  • briefing staff to look out for anyone behaving suspiciously or for suspicious-looking vehicles
  • ensuring that all visitors have their identities checked
  • installing a CCTV system

8. Chemical, biological and radioactive threats

There have only been a few examples of terrorists using CBR materials. The most notable were the 1995 sarin gas attack on the Tokyo subway and the 2001 anthrax letters in the United States. In 1996 in the US, an al-Qa’ida operative was sentenced for conspiracy to murder for his part in planning attacks using ‘dirty bombs’, which contained radioactive material.

The impact of a CBR attack would depend heavily on the success of the chosen method and the weather conditions at the time of the attack. The first indicators of a CBR attack may be the sudden appearance of powders, liquids or strange smells within the building, with or without an immediate effect on people.

Remember to apply personnel security standards to contractors, especially those with frequent access to your site.

9. Insider threat

Occasionally threats to companies and organisations come from within. Whether it is from a disaffected member of staff or an employee that has misrepresented themselves, there is more opportunity to disrupt or cause damage (whether physical or reputational) from the inside.

The risks posed by the insider threat can be lessened by carrying out thorough pre-employment checks and by having a strong security culture. The CPNI provides detailed guidance on personnel security.

10. Cyber threat

In the 21st century, one of the greatest threats to a company or organisation is from cyber attacks. The effects can often be devastating: the loss of crucial data, or a reduction in operating efficiency, or even closure.

Your senior management must assess the risk appetite of the company or organisation. But it is vital that everyone in your workplace understands the risks posed by cyber attacks.

A cyber attacker may not reveal themselves or even the nature of the attack. An attack may have no obvious adverse effects, but will extract information or data from your networks.

Read the advice on Cyber essentials or visit the CPNI Website.

11. Further information and advice