MOSCOW — President Vladimir Putin said Wednesday that Russian authorities know the identities of the two men accused by Britain of carrying out a nerve agent attack on a former spy, but he added that they are civilians and there is “nothing criminal” about them.

The statement by Putin marked an abrupt shift from Russia’s earlier position on the poisoning case that has damaged relations between Moscow and the West. Initially, Russian officials said they had no idea who the men were and questioned the authenticity of some of security-camera photos and video released by Scotland Yard showing them in London and Salisbury, where the poisoning took place.

Britain last week charged two men in absentia, identifying them as Alexander Petrov and Ruslan Boshirov. Authorities alleged they were agents of Russia’s military intelligence agency known as the GRU and accused them of poisoning former Russian spy Sergei Skripal and his daughter, Yulia, in Salisbury on March 4.

Britain blamed the Russian government for the attack, an allegation that Moscow has vehemently denied.

Putin on Wednesday did not try to dispute the British evidence, but he insisted the men were innocent.

“We know who these people are, we have found them,” Putin said in response to question at panel for an economic conference in Vladivostok in Russia’s Far East. “There is nothing special or criminal about it, I can assure you.”

Asked by the panel’s moderator if the men work for the military, Putin replied that they are “civilians” and called on the men to come forward and speak to the media.

Kremlin spokesman Dmitry Peskov later told reporters that Putin never met the suspects in the poisoning and that Russia did not investigate them but merely “checked the reports.”

Ever since British authorities made their initial accusations, Russian officials and media sought to discredit them, either deriding their statements or offering alternative explanations

The Skripals’ poisoning by the deadly nerve agent Novichok triggered a tense diplomatic showdown. Britain and more than two dozen other countries expelled a total of 150 Russian diplomats, and Russia kicked out a similar number of those countries’ envoys.

The attack left the Skripals hospitalized for weeks, and two other area residents became seriously ill months later. One of them, a 44-year-old woman, later died.

British Prime Minister Theresa May said the attack was carried out by officers of the GRU and almost certainly approved “at a senior level of the Russian state.”

Her spokesman, James Slack, rejected the claim the men were civilians, saying they were GRU officers “who used a devastatingly toxic illegal chemical weapon on the streets of our country.”

“We have repeatedly asked Russia to account for what happened in Salisbury in March and they have replied with obfuscation and lies,” Slack said. “I have seen nothing to suggest that has changed.”

Putin’s abrupt shift from earlier official statements on the case fits a pattern by the Russian leader.

When troops in uniforms without insignia first appeared on the streets of Ukraine’s Crimean Peninsula in 2014 prior to its annexation, Putin insisted that they were not members of the Russian military, but merely local volunteers. Weeks later, Putin said there were Russian troops present there under a treaty with Ukraine that allowed Russia to leave a naval base in Crimea.

Similarly, Putin initially dismissed accusations of Russian state-sponsored hacking in the U.S. election system, but he later admitted the possibility that it was the work of some “patriotic-minded” Russians, although he denied that any of them had been directed by the Kremlin.

READ MORE: U.S. to impose sanctions on Russia over nerve agent attack on former spy

Ever since British authorities made their initial accusations of Russian government involvement in the poisoning, Russian officials and media sought to discredit them, either deriding their statements or offering alternative explanations.

After British authorities released photos and video of the men, Russian Foreign Ministry spokeswoman Maria Zakharova alleged that two of the photos in a London airport had been doctored. She later walked back that statement, expressing frustration that British authorities had not shared the files with their Russian counterparts, leaving Moscow “guessing” about what really happened in Salisbury.

Moscow also questioned the origins of the nerve agent involved in the attack, saying it was not proven that the substance was developed by Russia and arguing that other countries, including Britain, had the capacity. Although Novichok is said to be extremely lethal, the Skripals survived, and Russian authorities even questioned why British officials put down the Skripals’ pets.

When charges were brought against Petrov and Boshirov last week, Russian media reports appeared to tacitly accept that they were Russians but rejected the possibility that they were sent by the GRU, saying the operation was too clumsy to have been done by well-trained agents. That argument centered on how they made themselves overly visible to surveillance by taking the train to Salisbury and walking through the city, rather than going by private car.

“There have never been and never will be such stupid people in Russian intelligence,” journalist Nikolai Dolgopolov, who has written widely about spies, said on Vesti Nedeli.

Skripal’s niece Viktoria, who lives in Russia and often voices pro-Kremlin arguments on Russian television talk shows, told the Interfax news agency Wednesday that she knows “through her own sources” that the men identified as Petrov and Boshirov are “ordinary men” who are “shocked” by the accusations.

She claimed that Petrov was not in Britain around the time of the poisoning but did not elaborate on how she knew that.

The case, with its chilling details, echoes the 2006 murder of Alexander Litvinenko, a former Russian agent who died after drinking tea laced with radioactive polonium-210 at a London hotel. Britain spent years trying in vain to prosecute the prime suspects, Andrei Lugovoi and Dmitry Kovtun.

A British inquiry concluded that Litvinenko had been killed at the behest of the Russian state, probably with the president’s knowledge.

The Russian government rejected the accusations and was quick to throw its support behind the men. Lugovoi ended up in the Kremlin-friendly Liberal Democrat Party and since 2011 has been a member of the lower house of parliament, enjoying immunity from any prosecution.