1. Various of decontamination clothing and shelters demonstration
2. Various of police cars on motorway
3. Night shots of emergency services outside Heathrow airport
4. Various of airport interiors, policemen questioning travellers
5. UK civil training exercise "Trump Card"
6. SOUNDBITE: (English) Dr David Claridge, Intelligence Analyst:
"I'm sceptical that Al-Qaida will try to chemical or biological weapons. They've had a lot of success in the past using more conventional means. There's really no reason for them at this stage for them to be thinking of using chemical or biological weapons."
7. British Army nuclear biological and chemical defence Regiment on exercise
8. SAS soldiers by airport fence during Stanstead hijack
Britain is preparing for a major terrorist attack involving nuclear, chemical and biological weapons following the suicide missions in New York and Washington on September 11 that destroyed the World Trade Center and severely damaged the Pentagon.
It also follows a World Health Organisation warning on Tuesday of the threat of biological weapons.
America has already grounded crop-dusting planes as the effects of germ warfare delivered by such a method could be devastating.
Britain's National Health Service is buying decontamination units and protective suits on an unprecedented scale.
Mass production of anthrax vaccine in the United Kingdom is also underway.
Anything from HIV to the bubonic plague could be used by terrorists, but the attention of military and scientific experts has focused on anthrax and smallpox.
The last known case of smallpox was 24 years ago and neither anthrax nor smallpox is countered by vaccination programmes in Britain.
Smallpox has been eliminated worldwide but supplies of the virus exist for scientific purposes in two places - Atlanta in the US and in Russia.
There are fears that Russia is unable to account for all its supplies and that there are stocks of the virus that have been traded on the black market.
It is thought that just a cupful of a genetically engineered version of smallpox, unleashed in a city, could kill thousands.
Anthrax has attracted much attention because, in its spore form, it could be inhaled in large numbers which would lead to the usually fatal condition of inhalation anthrax.
Anthrax could be spread through an aerosol from an aeroplane and is relatively safe for terrorists to handle.
In its early stages, inhalation anthrax is difficult to distinguish from the common cold which means that by the time the diagnosis is made, the initial exposure could have spread to tens of thousands.
At Britain's Heathrow airport recently a biological terrorism alert caused the evacuation of Terminal Three, one of the airport's busiest.
A passenger had tried to board an aircraft with an unknown substance labelled bio-hazard, government scientists examined it and found it harmless.
Emergency services training for civil and emergency personnel in gas attacks such as Sarin, has been stepped up in Britain in the last two years.
In real life a huge area of London would have been contaminated involving many thousands of homes, major roads and railway lines, testing Britain's contingency plans to the limit.
Some analysts believe that fears that Osama Bin Laden's forces will use chemical and biological weapons are unfounded.
While chemical and nuclear weapons are expensive and require sophisticated machinery and materials, all it takes to grow bio-war agents is a vial of the bacteria and a batch of culture.
The equipment needed to culture micro-organisms is said to be found inside the everyday fridge and the local supermarket.
For this reason, germ technology has been referred to as the poor man's nuclear bomb.
The first recorded attempts of biological warfare were in Biblical times when soldiers put dead bodies down wells to poison enemy villages.
But a Sarin gas attack by the Japanese religious cult Aum Shinrikyo in 1995 served as a wake-up call to the world of the threat from chemical and biological weapons.
The cult followers released the gas in the confined spaces of Tokyo's underground where it would be dispersed more slowly and have maximum effect.
The attack killed 12 people and more than 5,000 were affected.