How likely is a chemical attack on the UK?

Peter Bennett, from security consultancy Covenant, discusses the possibility of chemical attacks on critical national infrastructure, examining both the short and long-term effects

It is more than likely that all countries in the world contain some groups and individuals who harbour a desire to perpetrate an attack against something or somebody. Amongst those people there are some who favour the use of chemicals as a means to inflict harm. So what exactly is the threat?

There is inherent threat in much of our daily lives through the activities we undertake, from accidents and disasters, and of course from deliberate acts designed and intended to cause harm. We discuss chemical attacks in terms of a large scale event resulting in a high number of fatalities, numerous injuries and major disruption – in essence the question posed seeks to provide some sort of considered answer to the likelihood of an event like that taking place on our soil.

So how do we assess threat? Simply put, a threat must be credible for it to have a chance of materialising. This credibility is driven by three factors: the intent of a threat actor to deliver; the opportunity for that threat to be delivered; and the capability of a threat actor to deliver. If all three factors are present then you can consider the threat to you as credible.

Acting with intent
Intent depends very much upon the beliefs and motivations of the threat actor. Extremist views can be strongly affected by individual and group ideals and perceptions of other external influences. The UK government is attempting to reduce the threat from terrorism in the UK through its counter terrorism programme, referred to as ‘CONTEST’. One of the strands of this is ‘PREVENT’, which aims to steer those at risk of radicalisation away from joining terrorist organisations – however this programme is largely focused upon Muslim communities. There are those who just won’t be diverted from their particular course and will continue to develop plans regardless. ISIS and other terrorist organisations clearly use the UK foreign policy as one justification for their actions, whilst other attacks have been motivated by different issues, such as the politics of hate.

David Copeland, the London ‘Nail Bomber’, harboured neo-Nazi views and in 1999 placed three explosive devices in London, aimed successively at the black community in Electric Avenue, Brixton, the Bangladeshi community in Brick Lane, and the LGBT community at the Admiral Duncan pub, in Soho. He was also exploring a bio development and was trying to produce material in home-made petri dishes. His stated political aim was to instigate a ‘racial war’ and create an upsurge of support for the British National Party.

Anders Breivik, who was responsible for the July 2011 attacks in Oslo and Utoya, has been described as extreme right wing and Islamophobic, yet described himself as a ‘conservative nationalist’. He successfully avoided discovery by the authorities by creating an agricultural business allowing him access to purchase certain materials. He obtained 100kg of chemicals from an internet site and later bought approximately six tonnes of chemicals usually associated with fertiliser.

Very recently, Thomas Mair, reported as the person responsible for the murder of Labour MP Jo Cox, gave his name in court as ‘death to traitors, freedom for Britain’. There are suggestions he subscribed to a magazine with pro-apartheid views and was against the expansion of Islam and multi-cultural societies.

When the opportunity arises
Opportunity varies according to several different factors, but if we look at it simply in terms of ‘are there places where a chemical attack could be deployed?’, then the answer is equally simple. Routine access to public spaces where large numbers of people gather is always going to be possible to some degree, even if there are entry requirements. Potential attackers will assess site attractiveness, the likely impact of their attack and the most effective methodology for the level of opportunity available amongst their planning considerations.

The UK Critical National Infrastructure (CNI) is divided into thirteen activity sectors. The most likely aim of a chemical attack will be to cause mass casualties, but the nature of business activity at many of these CNI sites does not attract large numbers of people, so they are less attractive as a target for a chemical attack. However, with the broad range of activities across the CNI sectors these sites may be considered for other attack methodology, depending upon the attacker’s chosen aims and any perceived or identified site vulnerabilities.

It is also significant to look at whether a threat actor has access to sufficient materials and equipment necessary to prepare and deliver an attack of this nature. A large scale attack requires large amounts of materials and it is during the acquisition phase that attackers can be most vulnerable to detection. This can have an impact upon methodology and their perception of likelihood of success, but it also leaves a trail of information for the authorities. This trail has been misunderstood before, with indicators being discovered in a post-incident investigation rather than early enough to disrupt an attack. Anders Breivik is a good example. The German Wings pilot, although not considered a terrorist, is another, as there were several triggers in his behaviour which, if identified sooner, may have averted the crash.

Capability varies enormously between threat actors. Knowledge is key – you have to know what you want to do and how to do it if you require a chance of success. The science of chemical properties, how to produce certain chemicals and information about those materials used as chemical weapons is already available and provided in great detail.

Unsurprisingly, the internet provides huge amounts of information to fill knowledge gaps, with a straightforward search able to deliver very detailed information on the range of chemicals, their properties and their availability. Instructions on how to prepare them are widely accessible and the hazards involved widely documented, but that is only part of the picture. Some of the more well‑known chemical weapons, such as Sarin, are dangerous to manufacture safely even in small quantities and a significant level of knowledge and skill would be needed to manage the risks posed in their production.

Resources are the next vital element. Small quantities of some highly toxic materials can be produced in a basic chemistry laboratory or illicit kitchen lab set up and the raw materials for many of these are not that difficult to obtain. However, this depends a great deal on the chosen substance, as many of these require precursors or generate by-products which in themselves are highly toxic, flammable and/or explosive, so they can be just as unpleasant as the final material. This hazard is regularly demonstrated in illicit drugs laboratories where the participants have managed to blow themselves up or set their rooms alight.

Attack planning in tokyo
This is the point where capability becomes a problem for attack planning. As with biological attacks, the intent to attack us is present, the opportunities to do so can be identified, the knowledge required to prepare the chosen materials is also available and the materials themselves can be relatively easy to acquire. However, there are two major hurdles to overcome and it is these two issues which have the greatest effect on the likelihood of a large scale attack being perpetrated and, most importantly, being delivered with a high degree of success.

A look at the attacks in Matsumoto and on the Tokyo subway system, perpetrated by the Aum Shinrikyo group in 1994 and 1995, sheds some light on these difficulties. Both of these attacks used Sarin as the weapon of choice. In 1994, in Matsumoto City, Nagano, members of the Aum Shinrikyo group released Sarin gas into the atmosphere in the vicinity of a pond, resulting in the deaths of seven people and leaving 274 others seeking treatment.

On 20 March 1995, members of the same group launched an attack on the Tokyo subway system in the early morning rush hour, targeting a number of different rail routes. They used liquid Sarin transported in sachets, which they pierced with sharpened umbrella tips on the floor of the train carriage before making good their escape. The Sarin leaked out and began to evaporate quickly, with rapid effects. Ultimately there were 12 recorded deaths, with over 5,000 people being treated for exposure, some in a critical state, others described as ‘worried well’.

In the subsequent investigation it was revealed that Aum Shinrikyo had manufactured the Sarin used in the subway attack at their own facility, which comprised a three storey purpose made manufacturing plant, constructed over a period of years at Yamanashi, near Mount Fuji. They also had facilities in several other countries and had been working with Sarin, as well as other harmful agents, for a number of years. The group was well-funded and resourced, with extensive facilities and expertise utilised over a significant period of time.

Some time later, a United States sub‑committee estimated that, had the group chosen a more effective delivery method for their Sarin, many thousands, perhaps tens of thousands of people would have been killed.

Chemical agents have a toxicity threshold which must be reached before they can have a lethal effect. Obviously this varies according to the agent, but it is without doubt that to achieve this level across a large, public, open area or network can be very challenging. Additionally, dispersal of the agent usually occurs very quickly, so enormous quantities are required to reach lethal dose thresholds over large areas. If your intent is to cause mass casualties then the amount of toxic material required would be very large indeed.

Developing a system which will successfully deploy a highly toxic material into a public space or network in sufficient concentration to reach lethal thresholds is also challenging. To release an agent in sufficient quantities to cause mass casualties represents a difficult technical task that requires knowledge and resources but it is achievable. The use of Sarin in Syria has been widely reported, with the use of Chlorine in Iraq and suggestions of Mustard also being deployed there further supporting this.

Long-term consequences
It is worth briefly discussing impact, too. Although a slightly different type of attack, the anthrax letters sent out in September and October 2001 in the United States demonstrate how even a relatively unsuccessful attack in terms of casualties can have significant and long‑lasting consequences.

It is believed that about 11 of these letters were sent, although only four were ever recovered, each containing a very small amount of anthrax spores. There were five deaths and at least 17 people treated for effects of anthrax inhalation. The four recovered letters all passed through the postal facility at Hamilton, New Jersey on their way to their ultimate recipients, contaminating that facility as they did so.

The clean-up programme that ensued was extensive, with dozens of buildings affected. Brentwood postal facility took 26 months to decontaminate at a cost of $130 million, Hamilton cost $65 million to clean up and was closed until 2005. One FBI estimate put the overall cost at over $1 billion.

To this day, people are well aware of postal deliveries containing suspicious white powders, with significant numbers of incidents being reported to authorities year on year.

Public fear of being exposed to a harmful substance is a powerful driver in influencing behaviour. Should there be a large scale chemical attack at an iconic location, a popular crowded place or perhaps a large transport hub, there will be an effect upon the willingness of individuals to visit or transit through that location for some time, although eventually that fear will decline. How many will be concerned and for how long is very hard to define. Costs to clean up will be high, that is without doubt.

So what of the likelihood then? This question really needs to be clarified. It should ask: ‘How likely is a large scale chemical attack in the UK, and will it be successful in achieving mass casualties?’. Based on available information and the limitations as they are understood right now, the likelihood of there being a large scale chemical attack on the UK can currently be considered as low, but the impact of such an attack would be very high.

The likelihood of such an attack resulting in mass casualties is more difficult to assess as there are many variable factors to be applied. Much of the effect of a released agent is dependent upon where it is released and the weather conditions prevailing there at the time. Public reaction to it is also relevant, as it is probable that injuries and even fatalities could occur as large numbers of people rush to escape a threat, even if they are not actually affected by the agent itself.

Our emergency response is important too. Ongoing efforts to improve and refine emergency response capabilities, supported by continued public awareness, industry compliance and collaboration, academic engagement and a host of other initiatives all add value to our resilience and the level of deterrence we present. Complementing and integrating those with proportionate security regimes and sensible, effective regulatory controls is key to keeping the threat and likelihood as low as we can.


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