Never-before-seen CCTV footage of two Russian men suspected of poisoning Sergei and Yulia Skripal with Novichok has been released by detectives.
One of the clips shows the pair walking past a petrol station near the home of the former Russian spy and and his daughter, police said.
The Skripals were found slumped on a bench in a local park on March 4 this year following the attack.
Another clip shows the suspects taking pictures, smiling and “looking pleased with themselves” as they walk around the city before heading back to the train station later on in the day.
Police also released pictures of a specially-made model of the counterfeit Nina Ricci perfume bottle containing the nerve agent in hopes that anyone who saw it at the time may come forward.
The original bottle led to the death of Wiltshire resident Dawn Sturgess in July after her partner, Charlie Rowley, discovered the discarded item, unaware of its toxic contents which Sturgess sprayed on herself.
Deputy Assistant Commissioner Dean Haydon told Panorama that the amount in the bottle had the potential to kill “thousands”.
The fresh images come as a police officer who was poisoned with the deadly substance after the attack told of his ordeal and how the experience left him “petrified”.
In his first interview since the incident, Detective Sergeant Nick Bailey told BBC’s Panorama: “My pupils were like pin pricks. And I was quite sweaty and hot. At that time I put it down to being tired and stressed.”
The 38-year-old had been wearing a hazmat suit to search to Skripals’ house after the attack, but was poisoned after touching the front door handle, where the Novichok was sprayed.
He began to feel ill after a short while and his condition deteriorated two days later, when he was rushed to hospital.
“Everything was juddering, I was very unsteady on my feet...my whole body was dripping with sweat.”
Medics later told him he had the nerve agent in his body, which he said left him “petrified” knowing how the Skripals - who were both in comas next door - had been affected by it.
The father said: “I don’t know whether, if it’s gone through the gloves, I don’t know whether, I mean, I could have adjusted my face mask and my goggles whilst I was in the house with it being on my hand,
“It’s such an outrageous, dangerous way of doing something that it angered me as well because any number of people could have been affected by that.”
He was discharged from hospital two-and-a-half weeks later, but him and his family were forced to get rid of all their possessions, including their home and cars.
The Skripals are believed to be in a safe house under the protection of the British government, and the investigation into the poisonings is ongoing.