The world could face more chemical attacks in the wake of the Novichok poisoning now people can learn how to make such weapons online, the Defence Secretary has warned.
Ben Wallace said access to such knowledge "can turn what might be ambitions into realities" for a whole range of attacks.
Speaking to the PA news agency nearly three years after the attempted killing of Sergei Skripal in Salisbury on 4 March 2018, he said Russia remained an "adversary" of the UK.
The then 66-year-old former Russian spy-turned-double agent for MI6 and his 33-year-old daughter Yulia were left seriously ill after coming into contact with the deadly nerve agent.
Dawn Sturgess, 44, died after she and her partner Charlie Rowley fell ill in nearby Amesbury months later.
She had come into contact with a counterfeit Nina Ricci perfume bottle believed to have concealed the lethal chemical for use against the Skripals before it was discarded.
A pre-inquest review into her death is due to take place at the end of this month.
Detective Sergeant Nick Bailey, from Wiltshire Police, was also treated after coming into contact with the substance and has since left the force.
Mr Wallace said: "Dawn Sturgess lost her life as a result of this attack and potentially hundreds of people's lives were put at risk given the weapon that was used."
He added: "Now you can find out how to make chemical weapons on the internet.
"That proliferation means that many people in the world have access to knowledge that can turn what might be ambitions into realities, around everything from conventional attacks to CBRN (chemical, biological, radiological, nuclear) capabilities."
His comments come as a chemical and biological weapons expert warned that rogue states and terror groups could even try to use coronavirus or similar viruses for attacks in the future.
Hamish de Bretton-Gordon told PA that COVID-19 has shown how a "not very virulent pathogen can bring the world to its knees" and this will not go "unnoticed by bad actors".
Mark Andrews, chairman of Wiltshire Police Federation, said extra chemical and biological training introduced after the Novichok attack has equipped officers with much-needed skills to thrive in battling a health crisis.
The family of Ms Sturgess previously called on the Government for answers but there are fears they may never get justice unless two men, known as Alexander Petrov and Ruslan Boshirov, who are accused of carrying out the attack, leave Russia.
The pair are still wanted by UK police after the Crown Prosecution Service authorised charges against them.
Counter-terrorism police are still appealing for witnesses and anyone with information to come forward, saying this week that they "remain as determined and committed as ever to bring those responsible for this attack to justice".
Last month, Mr de Bretton-Gordon told Forces News "we should think of weaponised biology as no less of an existential threat in the 21st century to the planet, than weaponized atomic science in the 20th century".
The Defence Secretary also warned in February of a "growing threat" of international chemical and biological attacks, with some regimes willing to use such weapons on their own people.
Cover image: Defence Secretary Ben Wallace (Picture: PA).