The investigation into the attempted murder of Sergei Skripal and his daughter Yulia appears to be focusing on five key scenes: his home, the spot where the pair fell ill, the two places they ate and drank before their collapse, and his BMW car.

Skripal’s road on the outskirts of Salisbury remains sealed off and detectives and experts in protective hazmat suits continue to comb his modern red-brick home and question neighbours and his friends.



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On Wednesday, investigators in hazmat suits returned after dark to the bench in the Maltings shopping centres where Skripal, 66, and Yulia, 33, became ill and removed items in plastic bags.

Police have also launched a specific appeal for anyone who saw the Skripals in the BMW in the 45 minutes before they arrived in the Maltings on the afternoon they fell ill – Sunday 4 March. The Zizzi restaurant and Mill pub, which the pair visited, are still cordoned off.

Hundreds of officers including counter-terrorism detectives, local police, forensic experts, intelligence analysts and the military are involved in the search for evidence of who exactly carried out the attack – and how.

Hamish de Bretton-Gordon, a former commander of the now-disbanded Joint Chemical, Biological, Radiological and Nuclear Regiment, said he believed the nerve agent novichok that was used was probably in powder form. “That seems to be the most plausible thing,” he said.

Theories have been swirling around Salisbury about how the novichok may have been delivered, including on the BMW’s door handles, steering wheel, or in its ventilation system. But the Guardian understands that the police officer taken ill, DS Nick Bailey, may have fallen ill after visiting his home, suggesting that the house remains crucial.

Officers in protective suits work near the bench in Salisbury where Sergei Skripal and his daughter Yulia were found. Photograph: Henry Nicholls/Reuters

De Bretton-Gordon said it was “plausible” that the nerve agent could have arrived in the post or in a gift. “You open a letter and the stuff goes all over the place,” he said.

“It is equally plausible that an agent could have delivered it. You only need to drop a small amount in someone’s pocket or brush past them.”

Scotland Yard, clarifying elements of the case’s timeline, confirmed Yulia arrived in the UK at 2.40pm on 3 March – 24 hours before the pair fell ill.

Officers are examining many hundreds of hours of CCTV footage to trace Yulia’s movements before and after she arrived in Salisbury. However, it seems unlikely that the nerve agent would have been sent into the UK on or with her. Had something gone wrong on a crowded international flight, it would have been a disaster.

It is clear the investigation remains very fluid.

Quick Guide Timeline: the poisoning of Sergei and Yulia Skripal Show 1.30pm Police have confirmed that Skripal and his daughter were in Salisbury city centre by 1.30pm. It is not known if they walked from his home or whether they drove or were driven in. Between 1.30pm and around 4pm Skripal and his daughter strolled around Salisbury and visited the Zizzi restaurant on Castle Street and the nearby Mill pub. They are believed to have been in Zizzi for about 40 minutes from 2.30pm. 3.47pm A CCTV camera at Snap Fitness in Market Walk captured two people initially thought to be Skripal and his daughter. The woman appeared to be carrying a red handbag. Later it became clear the pair were probably not the Russian and his daughter. Police have been keen to speak to the couple. 4.03pm The same camera caught personal trainer Freya Church. She turned left out of the gym and in front of her saw Skripal and the woman on a bench at the Maltings shopping centre. She said the woman had passed out and the man was behaving strangely. Church walked on. 4.08pm Footage that emerged on Friday from a local business showed that people were still strolling casually through Market Walk. Approx 4.15pm A member of the public dialled 999. The Friday footage shows an emergency vehicle racing through the pedestrianised arcade shortly after 4.15pm. A paramedic also ran through. Police and paramedics worked on the couple at the scene for almost an hour in ordinary uniforms. 5.11pm The woman was airlifted to hospital; Skripal was taken by road. 5.13pm Images taken by a passerby show that officers were still clearly unaware of the severity of the situation. They did not have specialist protective clothing and members of the public also strolled nearby. 5.48pm Police told Salisbury Journal they were investigating a possible drug-related incident. At about this time officers identified Skripal and his daughter and by Sunday evening they were at his home – in normal uniform or street clothes. At some point DS Nick Bailey, now seriously ill in hospital, visited the Skripal house, but it is not known where he was contaminated. Approx 8.20pm Officers donned protective suits to examine the bench and surrounding areas. By 9pm Officers were hosing themselves down. It was not until the next day that a major incident was declared. Photograph: Ben Stansall/AFP

Attention seemed to home in on the BMW on Thursday – four days after the pair were taken ill – when teams of Met counter-terrorism officers and military experts in hazmat suits arrived at the Ashley Wood recovery garage on the Churchfields industrial estate in Salisbury to examine the car and take it away. Paramedics stood by while the work was done.

Eight days after the collapse on Monday, officers and troops in hazmat suits appeared in the village of Winterslow, six miles north-east of Salisbury where they worked on an Ashley Wood van. Later that day, back in the city, the first floor of the Sainsbury’s car park was cordoned off and a police tent set up covering the car park’s ticket machine.

It is now known that this is where the Skripals parked at approximately 1.40pm on Sunday 4 March before going to the Mill Pub then on to the Zizzi restaurant.

Father and daughter stayed at Zizzi until about 3.35pm and emergency services were called to the bench in the Maltings where they were taken ill at 4.15pm.

Police are particularly keen to hear from anyone who saw the Skripals in the BMW – registration plate HD09 WAO – between 1pm on Sunday and the time they arrived in the city centre. They are also working hard to track the pair around Salisbury during the 40 minutes after they left Zizzi and before they fell ill on the Maltings bench.