Kremlin critic Alexey Navalny said on social media on Friday that he had been informed of new criminal charges against him.
Mr. Navalny, 47, is already serving sentences in a penal colony totalling more than 30 years on charges including extremism, which he denies, and has spent much of the past two years in solitary confinement for a range of alleged misdemeanours.
In comments issued through his associates, he said he had now been charged under Article 214 of the penal code, which covers vandalism.
“I have no idea what article 214 is, and there’s nowhere to look. You’ll know before I do,” he said on his Telegram channel.
“They really do initiate a new criminal case against me every three months. Rarely does an inmate confined to a solitary cell for over a year have such a vibrant social and political existence.”
Mr. Navalny is by far the best-known figure in Russia’s splintered opposition; supporters cast him as a Nelson Mandela-style figure who will one day be freed from jail to lead the country.
His political movement has been outlawed and its key figures have been jailed or fled abroad as part of a crackdown on dissent that has intensified since President Vladimir Putin sent his armed forces into Ukraine early last year, in what Moscow calls a “special military operation”.
Mr. Navalny was convicted in August of new charges relating to alleged extremist activity and sentenced to an additional 19 years on top of the 11½ years he was already serving. He rejects all the charges as politically motivated and designed to silence his criticism of the Kremlin.
Last month, three of his lawyers were placed on a register of “terrorists and extremists” by a financial watchdog, five weeks after being arrested on suspicion of belonging to an “extremist group”.
Mr. Navalny earned admiration around the world for voluntarily returning to Russia in 2021 from Germany, where he had been treated for what Western laboratory tests showed was a near-fatal attempt to poison him with a nerve agent in Siberia.
He was immediately arrested on arrival. The Kremlin denied trying to have him killed.