Two Russian nationals have been named as suspects in the attempted murder of former Russian spy Sergei Skripal and his daughter Yulia.
There is “sufficient evidence” to charge Alexander Petrov and Ruslan Boshirov over the attack in Salisbury, Scotland Yard and the CPS say.
They are thought to have been using the names as aliases and are about 40.
Mr Skripal, 66, and his daughter Yulia, 33, were poisoned with nerve agent Novichok in March.
Three months later, on 30 June, Dawn Sturgess and Charlie Rowley fell ill at a house in Amesbury, about eight miles from Salisbury.
Ms Sturgess died in hospital on 9 July. Mr Rowley was discharged from hospital on 20 July.
Sue Hemming, CPS director of legal services, said there was enough evidence “to provide a realistic prospect of conviction” and that “it is clearly in the public interest to charge Alexander Petrov and Ruslan Boshirov”.
The offences include conspiracy to murder Sergei Skripal; the attempted murder of Sergei Skripal, Yulia Skripal and Nick Bailey; the use and possession of Novichok contrary to the Chemical Weapons Act; and causing grievous bodily harm with intent to Yulia Skripal and Nick Bailey.
Ms Hemming said the CPS would not be applying to have the men extradited as Russia does not currently allow the extradition of its nationals.
Det Sgt Nick Bailey also fell ill after responding to the incident in Salisbury. Scotland Yard’s Assistant Commissioner Neil Basu, the head of UK counter-terrorism policing, said on Wednesday he “continues to make good progress but remains off work”.
Metropolitan Police said the two men had arrived at Gatwick Airport from Moscow on 2 March and stayed at the City Stay Hotel in Bow Road, east London before travelling to Salisbury on 4 March – where Mr Skripal’s front door was contaminated with Novichok.
Police said Ms Sturgess and Mr Rowley were exposed to Novichok after handling a contaminated container of perfume. Mr Rowley has told police he found a box labelled as Nina Ricci Premier Jour in a charity bin.
Mr Basu confirmed that the two cases were related, saying:”We have now linked the attack on the Skripals and the events in Amesbury which affected Dawn Sturgess and Charlie Rowley.
“It now forms one investigation. We do not believe Dawn and Charlie were deliberately targeted, but became victims as a result of the recklessness in which such a toxic nerve agent was disposed of.”
Prime Minister Theresa May is to make a statement in the House of Commons later to update MPs on the Salisbury investigation, Downing Street has said.