Russian opposition leader Alexei Navalny is missing, with reports he has been transferred from a penal colony to a high security prison facility

This move does fall within the judge’s orders at his sentencing in March, but his legal team allege the individual’s current location is unknown.

Navalny’s lawyers say he was transferred to a maximum-security prison as his verdict came into force, but they have no idea which one.

A court in Moscow sentenced the prominent opposition leader to a further nine years in prison in March for fraud charges, over allegations he had been stealing from his Anti-Corruption Foundation.

The U.S. is now calling on Russian authorities to allow Navalny access to his lawyers, to his legal representation, and to medical care.

This recent conviction follows a crack-down on Navalny’s supporters, other opposition activists and independent journalists, with the Kremlin desperate to publicly condone all dissent.

The opposition leader’s close allies have also faced criminal charges, with many fleeing the country to escape persecution.

Meanwhile, his anti-corruption foundation has been destroyed after being labelled an extremist organisation.

The alarm regarding his whereabouts was raised after Navalny failed to show up to a scheduled meeting with his legal team.