A prominent Russian activist and critic of Vladimir Putin who was flown to Germany for emergency medical treatment appears to have been poisoned, doctors said on Tuesday. 

The findings will add to concerns that Mr Putin’s regime is poisoning its opponents following the Novichok attack in Salisbury. 

Pyotr Verzilov, a member of the activist band Pussy Riot and publisher of a news website that is highly critical of the Russian justice system, was flown to Berlin at the weekend after falling mysteriously ill.

The 30-year-old suddenly became unwell after attending a court hearing in Moscow last week. He suffered a series of seizures on the way to hospital and temporarily lost his sight and hearing, along with the ability to speak and walk.

Mr Verzilov is now in intensive care at Berlin’s renowned Charite hospital, where doctors told a press conference on Tuesday he is out of danger.

“The impression and the findings that we now have, as well as those provided by colleagues from Moscow, suggest that it was highly plausible that it was a case of poisoning,” Prof Kai-Uwe Eckardt, the head of internal medicine at the hospital, said.

Mr Verzilov was suffering from anti-cholinergic syndrome, a condition in which certain neurotransmitters get blocked, Prof Eckhardt said. The rapid onset of his symptoms was highly indicative of poisoning.

It is unlikely doctors will be able to identify the poison at this stage, six days after it was ingested, he said.

There is no other plausible explanation for Mr Verzilov’s condition, Prof Karl Max Einhäupl, the director of the hospital and a leading neurologist, said.

Mr Verzilov was jailed for 15 days after he ran onto the pitch during last year’s World Cup final in Moscow along with other Pussy Riot activists.

He is co-founder of Mediazona, a news wesbite that focuses on human rights abuses in Russia’s judicial and penal systems. 

“I assume that he was deliberately poisoned and that it was either intimidation or even an assassination attempt,” Nadezhda Tolokonnikova, Mr Verzilov’s former wife and fellow Pussy Riot member told Bild newspaper.