The police officer who was left critically ill after being exposed to novichok at the home of the former Russian spy Sergei Skripal has spoken for the first time of the “emotional battering” he has suffered in the aftermath.

DS Nick Bailey, who was left critically ill after searching Skripal’s home on the night of the attack in March, said that while he had made a physical recovery, the psychological impact had been serious.

Recalling the moment he was told he had been poisoned with novichok, he told BBC Panorama: “Knowing how the other two [the Skripals] were … I was petrified.”

Facebook Twitter Pinterest Police stand outside the former home of former Russian spy Sergei Skripal in Salisbury. Photograph: Matt Cardy/Getty Images

“Physically, I think I bounced back pretty well.” he said, but of his emotional wellbeing, he went on: “That’s a different kettle of fish. That’s taken longer. I describe it as emotional battering and psychological impact. It’s taken longer to deal with just because of everything that has happened to us.”

In the same programme, the police officer leading the investigation said that the nerve agent attack could have resulted in thousands of innocent people being killed.

Deputy assistant commissioner Dean Haydon said detectives had recovered a “significant” amount of novichok in a fake bottle of perfume that was found three months after the attack on the Skripals. Asked how many people it could have killed, he said: “It’s difficult to say. You know, possibly into the thousands.” The fake bottle is believed to have been used to smuggle the novichok into the UK and to spray the nerve agent on to Skripal’s door handle.

Haydon has also described a “gotcha moment” when two suspects, who have been identified as members of Russia’s GRU military spy agency, were spotted on CCTV footage.

Play Video 0:34 Skripal poisoning: further video released of suspects – video

“We had seized over 11,000 hours of CCTV – that was a massive task,” he told BBC Panorama. “We were sifting through the CCTV and we had a kind of ‘gotcha’ moment when we identified the attackers. We were now on to them … I don’t think they expected to be captured on CCTV in the way that they were.”

Haydon said it was “completely reckless” to have used novichok. Asked if a third man may have been involved, he said: “Who else is involved is still very much subject to a live line of inquiry.”

On Thursday night, police released three more pieces of footage of the suspects in Salisbury on 4 March as part of their ongoing investigation. This shows them arriving at the train station, at a petrol station near Skripal’s home, just before police think that the novichok was placed on the door handle, and then walking over a bridge back towards the train station.

Facebook Twitter Pinterest Model of the perfume bottle released by police. Photograph: Metropolitan police/PA

Three months after the Skripals fell ill, two Wiltshire residents, Charlie Rowley and Dawn Sturgess, were exposed to novichok contained in the fake perfume bottle and Sturgess died. Police also released a model of the bottle on Thursday night and appealed for any information as to its whereabouts before it was found in Rowley’s home.

Bailey said that since the incident, he and his family had not been able to return home. “Not only did we lose the house, we lost all of our possessions, including everything the kids owned. We lost all that – the cars … we lost everything. And yeah, it’s been very difficult to kind of come to terms with that.”

He and two colleagues, dressed in protective suits, searched the house a few hours after Skripal and his daughter collapsed in Salisbury city centre on 4 March. “I was the first person into the house,” said Bailey. “We had to make sure that there were no other casualties. The house was in darkness. It just looked normal. There was nothing untoward.”

But shortly after leaving the house, Bailey began to feel unwell. “My pupils were like pinpricks. And I was quite sweaty and hot.” He had gone home, but was rushed into hospital. “Everything was juddering. I was very unsteady on my feet,” he said.

Bailey said he did not know how he came into contact with the novichok. “I don’t know … if it’s gone through the gloves. 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.”

Bailey remained conscious throughout his treatment. He said: “It was painful at the beginning … I had lots of injections. One of the Skripals was in the room right next to me. It was all guarded by the police.”

A scientist at the government’s defence, science and technology laboratory at Porton Down, identified only as Prof Tim, described the “jaw-dropping moment” when it was realised that novichok had been used in the attack on the Skripals. “I went through a number of emotions, from disbelief to anger,” he said. “It’s one of the most dangerous substances known. It’s quite unique in its ability to poison individuals at very low concentrations.”

• Panorama: Salisbury Nerve Agent Attack – The Inside Story, Thursday 8pm, BBC One