Kremlin critic Alexei Navalny has been transferred to a penal colony outside Moscow to serve his prison sentence, a public commission said on Sunday, weeks after he returned to Russia after being poisoned.

Navalny’s whereabouts had been unknown since Thursday when his allies learned that he was transferred out of one of Moscow’s most infamous jails to an undisclosed location.

Navalny, 44, was arrested on his return from Germany last month and has been sentenced to more than 2-1/2 years for parole violations that he said were trumped up.

He has been transferred to a penal colony in the Vladimir region, the Moscow Public Monitoring Commission that defends the rights of prisoners and has access to people in custody, said on its website.

The state news agency TASS specified that Navalny will serve his term in penal colony number 2 in the town of Pokrov, about 100 km (60 miles) east of Moscow.

Reuters pictures showed metallic grey buildings behind a grey fence and barbed wire inside the colony, as well as the gold domes of a church. A guard at the gate asked reporters to keep a distance of at least 100 metres (yards) if they wanted to film it.

Ruslan Vakhapov, a local activist of the prisoners’ rights group Jailed Russia, described conditions as particularly severe.

-In short, it’s a bad colony- Ruslan Vakhapov told Reuters by phone.

Many prisoners cooperate with the colony administration and help them to control other inmates closely, abusing them if they violate a strict daily schedule, Vakhapov said.

-If there is a need to prevent Navalny from communicating with others, nobody would talk to him- the activist said.

-(If anything happens), he wouldn’t be able to ask for help until his lawyer arrives- he added.

A duty officer who took a call at the prison declined to answer questions about Navalny.

Navalny will be quarantined as a precaution against the spread of coronavirus before joining other prisoners in the colony, the monitoring commission said, according to the RIA news agency.

Earlier on Sunday a Navalny ally, Leonid Volkov, called on Twitter for authorities to provide official information about his whereabouts and access to him by his lawyers.

Navalny, President Vladimir Putin’s most prominent critic, suffered a near-fatal poisoning in Siberia in August with what many Western nations said was a nerve agent. Navalny accuses Putin of ordering his attempted murder.

Putin has dismissed that, alleging Navalny is part of a U.S.-backed dirty tricks campaign to discredit him.