Putin critic Alexei Navalny has revealed where he is being held after he was moved to a new prison last week.
The Kremlin critic is currently detained in Russia‘s Vladimir region, according to a post on his Instagram which likens his current prison to a concentration camp.
Mr Navalny‘s location had been unknown after he was moved last week from the Kolchugino jail.
He is now at the IK-2 corrective penal colony in the town of Pokrov, which is about 60 miles east of Moscow.
In a post on Instagram the 44-year-old said: “Hi everyone from ‘Heightened control sector A’.
“I have to admit that the Russian prison system has managed to surprise me. I never imagined that it was possible to build a real concentration camp 100 kilometres from Moscow.”
Mr Navalny was jailed earlier this year for parole violations – although this reason was said to be politically motivated by most in the West.
He was sentenced to two-and-a-half years in prison, and can only communicate with the outside world through his legal team.
The Instagram post added that swearing was banned at the facility – with inmates largely sticking to the rules.
Rumours of violence were believable, he said, although he had not seen it himself.
Mr Navalny added: “There are video cameras everywhere, they keep watch on everyone and make reports for the slightest infractions. I think someone high up has read 1984 by Orwell.”
He also said he gets woken up every hour at night because he is a flight risk.
“But if you regard everything with humour, you can live here. So on the whole everything is fine with me,” he added.
Seen by many as an opposition leader, Mr Navalny returned to Russia earlier this year after he was treated in Germany having been poisoned with the novichok nerve agent.
The Kremlin has denied involvement in the poisoning.