Updated 2pm with Russian reaction below
British prosecutors on Wednesday identified two Russians who they accused of trying to murder former Russian spy Sergei Skripal and his daughter Yulia with a military-grade nerve agent in England.
Skripal, a former colonel in Russian military intelligence who betrayed dozens of agents to Britain's MI6 foreign spy service, and his daughter Yulia, were found unconscious on a public bench in the southern city of Salisbury on March 4.
Britain has blamed Russia for the poisonings and identified the poison as Novichok, a deadly group of nerve agents developed by the Soviet military in the 1970s and 1980s. Russia has repeatedly denied any involvement in the attack.
British prosecutors named the two suspects as Alexander Petrov and Ruslan Boshirov, who police said arrived in Britain from Moscow on March 2 at London's Gatwick airport on an Aeroflot flight and left on March 4. Police released images of the two men.
Neil Basu, Head of UK Counter Terrorism policing, said the two suspects were travelling under aliases but were around 40 years old and had genuine Russian passports.
"We would like to hear from anyone who knows them," Basu said. Russia's foreign ministry said the names given by Britain did not mean anything to them.
Basu said Novichok was sprayed on the front door of Skripal's house in Salisbury, where the two men were sighted on CCTV nearby. Basu said traces of Novichok contamination were found in the London hotel room where the two men had stayed.
"Tests were carried out in the hotel room where the suspects had stayed. Two swabs showed contamination of Novichok of levels below that which would cause concern for public health," Basu said.
A European arrest warrant has been issued for the two Russians, the prosecutors said.
The Russians are charged with conspiracy to murder Sergei Skripal and the attempted murder of Skripal, his daughter and Nick Bailey, a police officer who was taken ill while attending to the Skripals.
They are also charged with use and possession of Novichok, contrary to the Chemical Weapons Act.
“We will not be applying to Russia for the extradition of these men as the Russian constitution does not permit extradition of its own nationals," said Sue Hemming, director of Legal Services at the Crown Prosecution Service.
A British woman, Dawn Sturgess, died in July after coming across a small bottle containing Novichok near Salisbury where the Skripals were struck down. Her partner, Charlie Rowley, was also stricken.
Police said Rowley and Sturgess had found a counterfeit Nina Ricci Premier Jour perfume bottle which tests later showed had contained Novichok.
Russia says names of men accused over Skripal "mean nothing to us"
The Russian Foreign Ministry said that the names of two men accused by the British prosecutors for trying to murder the Skripals meant nothing to Moscow.
Foreign Ministry spokeswoman Maria Zakharova said the names of the two men "do not mean anything to us," adding that the case required careful analysis and therefore close cooperation between London and Moscow.
"A link is being made with Russia. The names published in the media as well as the photographs mean nothing to us," TASS quoted Zakharova as saying.
"We again call on the British side to move from public allegations and information manipulation to practical cooperation via law enforcement," she was quoted as saying by TASS.
Russia's envoy to the Organization for the Prohibition of Chemical Weapons (OPCW) said Moscow had nothing to do with the poisoning, RIA news agency reported.