NOVICHOK is a highly potent chemical poison described as the most deadly nerve agent ever made.
Soviet scientists created the family of 100 substances in a secret program at the height of the Cold War.
What was the Novichok programme in Russia?
Soviet scientists are believed to have run a secret chemical weapons programme during the latter stages of the Cold War.
In 1999, US defence officials travelled to Uzbekistan to help dismantle and decontaminate one of the former Soviet Union’s largest chemical weapons testing facilities.
The institute was staffed solely by Russians and it was only when they left in 1993, taking with them a vast amount of equipment and documentation, that what had gone in there began to emerge.
According to a defector, the Soviets had used the plant to produce and test small batches of Novichok, which were designed to escape detection by international inspectors.
Novichok, meaning “newcomer” in Russian, was developed by the Soviet Union in the 1970s and 80s.
The deadly nerve agent group were described as fourth-generation chemical weapons.
They were developed under a Soviet programme under the codename “Foliant”.
Russia has never officially acknowledged the existence of the Novichok program.
Most of what is publicly known about it comes from Vil Mirzayanov, a Russian scientist who worked for years in the Soviet chemical weapons program.
What exactly is Novichok and what does it do to the human body?
The chemical is said to be the deadliest nerve agent ever created and reported to be five times more potent than the notorious VX gas.
There are more than 100 formulations in known existence of the Novichok family and a small dose is enough to kill within minutes.
It was designed to be made of two relatively harmless materials which become fatal when mixed together, making it easier to transport under the radar.
Novichok agents, dispersed as an ultra-fine powder, belong to the class of inhibitors called “organophosphate acetylcholinesterase”.
They prevent the normal breakdown of a neurotransmitter acetylcholine which, when it builds up, causes muscles to contract involuntarily.
Because the victim’s heart and diaphragm aren’t functioning properly, this leads to respiratory and cardiac arrest.
Those affected usually die from total heart failure or suffocation as copious fluid secretions fill their lungs.
But even if they don’t die, the substance can also cause permanent nerve damage, leaving victims permanently disabled.
Was Novichok used in the Salisbury attack?
In March 2018, former Russian double agent Sergei Skripal and his daughter Yulia were found unconscious in Salisbury.
They spent many weeks in hospital but were eventually well enough to be discharged.
Porton Down scientists and the OPCW chemical weapons watchdog confirmed they were exposed to Novichok.
Detectives are said to believe it was smeared on Mr Skripal’s doorknob in a Kremlin-sponsored assassination bid.
Moisture in the air would have degraded the poison before they touched it, sparing their lives, experts claim.
In September police revealed names and photos of two Russian men wanted over the attempted hit on the Skripals.
Cops issued a European Arrest Warrant for Alexander Petrov and Ruslan Boshirov.
And the CPS said there was enough evidence to charge them with conspiracy to murder.
The suspects were caught on CCTV in Salisbury at 11.58am on the Sunday March 4 “moments before the attack”, police said.
What happens now?
British officials are set to face their Russian counterparts as they brief the United Nations Security Council on September 6, 2018.
Prosecutors will tell the UNSC that there is enough evidence to charge the two men suspected of being behind the nerve agent attack.
Russia is a permanent member of the Security Council and will be represented at the meeting alongside UK allies the US and France.
In an address to MPs, Prime Minister Theresa May claimed the suspects are officers from Russia’s military intelligence service the GRU.
Moscow continues to deny involvement in the attack.
Who was poisoned by the nerve agent in Amesbury?
Charlie Rowley, 45, and Dawn Sturgess, 44, were found unconscious at a property in Amesbury, eight miles from Salisbury, on June 30.
Dawn died in hospital but Charlie recovered and was discharged.
Tests at Porton Down labs showed the couple were exposed to Novichok.
They are thought to have stumbled across a discarded bottle used to carry the nerve agent which poisoned Soviet spy Sergei Skripal and his daughter, Yulia.
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How did Novichok make it to the UK?
According to Andy Oppenheimer, a biological and chemical specialist, the chemical could have been brought into the UK through an airport.
He told Sky News: “These things can evade detection if they are very small amounts and very well shielded, whether they are biological, chemical or a biological agent.”
After two suspects were named in an arrest warrant, police said the nerve agent was brought into Britain in a Ninna Ricci Premier Jour perfume bottle with a specially made poison applicator.
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