The two Russian men suspected by British intelligence of poisoning Sergei Skripal and his daughter Yulia in England in March shadowed the former double agent in Prague in 2014, Czech Radio (CR) has cited sources as saying.



In an October 10 report, CR cited unnamed Czech intelligence sources as saying that the Russians -- whom cybersleuthing group Bellingcat says it has unmasked as military intelligence officers Anatoly Chepiga and Aleksandr Mishkin -- visited Prague in 2014 and that Skripal was there at the same time.



"It looks like the Russians had a group of people that followed Skripal long before the attempt to assassinate him," the publicly funded Czech radio station quoted one source as saying.



According to the report, the two Russians used the same names as those on the passports British authorities said they used when they traveled to Britain shortly before Sergei and Yulia Skripal were poisoned: Ruslan Boshirov and Aleksandr Petrov.

British authorities allege that the two Russians smeared a Soviet-designed nerve agent called Novichok on the front door of Skripal's home in the English city of Salisbury on March 4, the day the former Russian intelligence officer spy and his daughter were found incapacitated on a bench and rushed to the hospital.



Both survived after weeks in critical condition, but Dawn Sturgess, a woman who authorities said came in contact with the poison after her boyfriend found a fake perfume bottle containing it, died in July.



Czech Foreign Minister Martin Stropnicky said before leaving his post in June that Skripal, who settled in Britain after he was released from Russian prison and sent West in a 2010 spy swap, has visited the Czech Republic and several other European Union countries to consult with their intelligence services.

Media outlets have reported that Skripal was in the Czech Republic in 2012. The New York Times has reported that he "met with Czech intelligence officials on several occasions and visited Estonia in 2016 to meet with local spies."



The Russian Embassy in Prague declined to comment on whether the two men had traveled to Prague, saying in an e-mail response that the "matter of border-crossing by foreign nationals is within the competence of the Czech Republic's corresponding state structures," CR reported.



The poisoning has added tension to already severely strained ties between Russia and the West, leading to additional U.S. and European Union sanctions on Moscow and to diplomatic expulsions of Russian and Western officials.



Russia denies involvement, but Bellingcat's findings have added to the evidence against Moscow. The British-based independent investigative group also says that Chepiga and Mishkin have made multiple trips to various parts of Europe and elsewhere in the past few years.



Russian President Vladimir Putin said on September 12 that the two men accused by Britain were civilians. In comments on October 3 in which he called Skripal a traitor and a "scumbag," longtime Soviet-era KGB officer Putin said that the former Russian spy "continued cooperating with some secret services" after he went West in the swap.



Skripal, a former colonel in the Russian military intelligence agency known as the GRU, was convicted of treason in 2006 by a Russian court and had been serving a 10-year prison sentence when the swap, in which 10 sleeper agents including Anna Chapman were sent home to Russia from the United States, took place.

With reporting by Czech Radio and Current Time TV