Another person is facing charges linked to the infamous Novichok poisoning in Salisbury in 2018, police announced on Tuesday.
Police have identified Russian man Denis Sergeev as a potential suspect in the ongoing investigation into the horrific attack from three years ago.
Recalling the details of the attack
The Salisbury poisoning was an attack – believed to have come from Russian authorities – on former double agent Sergei Skripal and his daughter Yulia.
Skripal was granted refuge in the UK following a spy swap between the US and Russia.
Both were hospitalised after coming into contact with the Novichok smeared on the handle of Skripal’s front door, while a police officer was also injured. All three later recovered.
Unfortunately, civilian Dawn Sturgess came into contact with the poison’s bottle three months later and died after spraying it on herself, unaware of its toxic qualities.
What do police suspect Sergeev’s involvement?
Sergeev is thought to have been the on-the-ground commander during the attack.
All the suspects in the case are said to belong to Russia’s largest foreign intelligence agency GRU, and Sergeev is believed to have been the senior Russian military intelligence officer on the case.
BBC Newsnight has claimed Sergeev is a major general in GRU while the other two men, Alexander Mishkin and Anatoly Chepiga, are colonels.
What do we know about Sergeev?
Aged around 50, Sergeev is thought to be in Russia along with the other two suspects.
He is allegedly a senior member of Unit 29155, a specialist team linked to sabotage, subversion and assassination.
It is believed he was also involved in a similar poisoning from 2015 in Bulgaria, where a Bulgarian arms dealer, his son and business partner, fell ill after toxic matter was smeared on their door handles, an attack comparable to the 2018 Salisbury offensive. They all survived after an intense illness.
What evidence is there?
Head of special crime and counter terrorism at the Crown Prosecution Service, Nick Price, said there was “sufficient evidence to provide a realistic prospect of conviction”.
Sergeev reportedly arrived in Heathrow on the day of attack on March 2 2018 using the name Sergey Fedotov at 11am.
He stayed in London until March 4, and reportedly worked with the other two men on a number of occasions in London that weekend, although police have not clarified where the group might have met up together.
He then left before 2pm that Sunday.
A figure of interest for some time
Sergeev’s role in the poisoning was examined by the investigative site Bellingcat back in February 2019 in a joint investigation with the BBC.
However, police noted that it was “challenging” building up evidence of his part in the attack.
The other two suspects Chepiga and Mishkin appeared on Russian TV in 2018 after they were identified, and said they only visited Salisbury to look at the cathedral, but Sergeev has not publicly addressed the ongoing suspicion about his involvement.
What will happen next?
The Crown Prosecution Service has authorised the charges against the men – conspiracy to murder, attempted murder, causing grievous bodily harm and use and possession of chemical weapon – but the three suspects cannot be formally charged unless they are arrested.
If Sergeev leaves Russia, the UK authorities will ask Interpol to arrest him.
But Russia has no intention of extraditing its citizens has continued to deny any involvement with the poisoning.
Pre-inquest hearings into Dawn Sturgess’ death are set to continue this week.
What do we still not know?
It is still unclear how Novichok came into the UK, and what happened to it between its use against Skripal in March and when Sturgess came into contact with it in June in Amesbury.
The UK police claim it will continue to investigate other suspects as well.
This article originally appeared on HuffPost UK and has been updated.