Two police officers who rushed to help the Russian former spy Sergei Skripal and his daughter after they were attacked with a nerve agent have described how emergency first responders and a passing doctor helped save the pair.

Sgt Tracey Holloway and PC Alex Collins, speaking in detail for the first time, said more people could have been injured in the novichok attack in Salisbury and expressed hope that the perpetrators would eventually be brought to justice.

The two Wiltshire officers spoke of their shock at realising they had been embroiled in an international incident and their surprise that they and many other first responders had not been contaminated.

Holloway and Collins began their shift at 3pm on 4 March, an hour and 15 minutes before the Skripals collapsed on a bench. There had been heavy snow during the previous few days and they had been very busy.

“We have a briefing at the start of a duty,” Holloway said. “We had just suffered the snow issues. I said to the team: ‘Let’s have a relaxed day, let’s not get too involved in anything. Have a good day.’”

They were at Bourne Hill police station in the city centre when the call came in at 4.15pm. “It was a medical tasking for two persons: a male and female slumped on a bench in Maltings shopping centre,” said Holloway.

“We responded on lights and sirens,” Collins said. “It only took us two minutes to get there. I drove through the pedestrianised area and over the bridge. The female [Skripal’s daughter, Yulia] was on the floor on her side. There was a member of the public, who turned out to be a doctor, helping her, maintaining her airway. I believe if that doctor hadn’t done that, she would have died.

“The male [Skripal] was in a very unusual position. He was sat on the bench, rigid, catatonic, staring into space. He was breathing but totally unresponsive. We tried to help medically and to find out what had happened. Our first thought was that it was drugs.”

Collins, a police medic, put on gloves to handle the patients. Holloway remembers examining Sergei Skripal’s wallet with bare hands. The officers handled both the Skripals.

Within minutes of arriving at the scene, the officers had put a cordon in place. “There were children around,” said Holloway. “We didn’t know what we had. It was an open area. We pushed people well back.”

The bench in Salisbury where Sergei and Yulia Skripal were found collapsed. Photograph: Ben Stansall/AFP/Getty Images

When they began to examine the Skripals’ possessions, they grew more puzzled. “We had been half expecting to get to the scene and say: ‘Yep, know that person, know that person.’ But it was like, hmm, don’t know these people and they are quite well-dressed,” said Collins.

“We looked at their wallets to try to find their ID. There was a phone with Russian writing on it. The names weren’t familiar. That was strange. It didn’t feel right. It wasn’t quite normal.”

The uniformed officers called CID and a duty inspector. They helped get the Skripals into ambulances. Sergei was still rigidly fixed in a sitting position, so it was hard to manoeuvre him on to a stretcher. CID officers attended. “They were like: ‘That’s fine, everything’s OK’, and off they went again,” said Holloway.

Detectives went to the Skripal house on the edge of town. One of them, DS Nick Bailey, was left critically ill after being exposed to novichok when he searched the property.

Meanwhile, Holloway took no chances with the scene. “There was a pile of vomit underneath the bench. I wasn’t happy about leaving that there because we didn’t know what could have been in it to make these people ill,” she said.

Firefighters were called and donned hazmat suits to work on the scene, not because they feared a nerve agent attack but because of the possibility that the drug fentanyl may have been involved. Holloway had recently attended a safety course at which the toxicity of fentanyl had been spelled out. “I remember talking to control and saying: ‘This may sound weird but I’m not happy about the vomit being left,’” she said.

Collins went off shift. Instinct told him to get changed and he left the clothes he had been wearing in his garage. “I’m glad I did that,” he said. “I was intending to have a shower but I was so knackered I just climbed into bed and fell asleep. I’ve got little kids and they were climbing all over me next day, so the missus wasn’t particularly happy with that when it all came out.”

The next evening – Monday 5 March – Skripal’s name emerged and cordons began to be set up in Salisbury around the spots that he and his daughter had visited. Holloway said: “At home you’re looking at the news going: ‘Oh, A&E has been closed, Zizzi has been closed. Bishop’s Mill has been closed. This could be quite big.’ My mum was phoning me all the time.”

Collins said: “Got a phone call two days after: ‘All your kit, everything you were wearing that day … can you bring it to the station? Wallet, watch, mobile, everything.”

Holloway said they heard that a nerve agent was involved from media reports. “We had both touched the Skripals. When we heard, it was like: ‘Wow, OK, this could be serious.’ But I wasn’t concerned for me. I knew I had touched both patients and if it was going to affect me it would have done by then.”

Like most people, the officers feared the Skripals would not recover. “When I heard that Yulia had woken from her coma I was elated,” said Collins. “The fact that both recovered was brilliant. It meant the attackers didn’t succeed. Lives were saved.”

But there was also huge sadness. Both knew Charlie Rowley and Dawn Sturgess, who were poisoned three months later after apparently coming upon a container of novichok disguised as a perfume bottle. Sturgess died after spraying the nerve agent on to her skin. “I thought it was over and done with, an isolated incident,” said Collins. “That one came out of nowhere, it was a bombshell.”

The two suspects caught on CCTV. Photograph: Getty Images

When in September images of the suspects were released and their bizarre cover story was proffered, the officers were angry. “I was angry that they had come here. I was trying to work back in my mind if I had seen them during that day,” said Holloway.

Both officers live in Salisbury, which makes the attack seem more personal. Collins said he was told they may have been watched by the hit team as they worked to save the Skripals. “It happened on my home turf,” he said. “It was attempted murder on UK soil. We want to see them brought to justice.”

Holloway lived close to the Skripal house, which is still undergoing decontamination. “I would go home to a crime scene. I was never really out of it,” she said. “I worked and then went home and had to show my pass to get into the estate. I did think about Sergei quite a lot. I used to wonder if I’d ever come across him in the street. I’m more upset for both of them. They can’t lead a normal life.”

Collins said: “We’re cops, we take it in our stride. We’ve been to countless incidents after that that can be just as distressing. They are not in the press, but we go to fatal collisions and all sorts of things. I put it to the back of my mind.”

They are proud of the job police did on 4 March. “I would like to say thank you to my team for being awesome that day,” said Holloway. “If it wasn’t for them, we may have had more people ill.”

Collins said: “You often look back and think I wish we’d done that better. I reckon we did our absolute best that day. I think we were very lucky we didn’t have more casualties.”