Imprisoned Russian opposition leader Alexey Navalny, whose whereabouts were not known for over two weeks, has been moved to a penal colony in the Arctic, allies said Monday.

The disappearance of Russia's most prominent opposition politician, who mobilized huge protests before being jailed in 2021, had spurred concerns from allies, rights groups and Western governments.

It signaled a likely prison transfer, which can take weeks in Russia as prisoners are slowly moved by rail between far-flung facilities.

"We have found Alexey Navalny. He is now in IK-3 in the settlement of Kharp in the Yamalo-Nenets Autonomous District," his spokesperson, Kira Yarmysh, said on social media.

"His lawyer visited him today. Alexey is doing well," Yarmysh added.

The district of Kharp, home to about 5,000 people, is located above the Arctic Circle. It is "one of the most northern and remote colonies," said Ivan Zhdanov, who manages Navalny's Anti-Corruption Foundation.

"Conditions there are harsh, with a special regime in the permafrost zone" and very little contact with the outside world, Zhdanov said.

Navalny was first jailed after surviving an attempt to assassinate him by poisoning. A court extended his sentence to 19 years on extremism charges, and ruled that he be moved to a more secure, harsher prison.

"From the very beginning, it was clear that authorities wanted to isolate Alexey, especially before the elections," Zhdanov also said.

Russia is scheduled to hold a presidential vote in March. President Vladimir Putin is expected to easily win a fifth term.

While Navalny's location was still unknown, Leonid Volkov, Navalny's chief of staff, said on social media that, "The fact that this is happening right now (although Navalny should have been transferred to another colony two months ago) — now that 'elections' have been announced and Navalny's team has launched the 'Russia without Putin' campaign — is 0% accidental and 100% directly political manual control from the Kremlin.

"It is no secret to Putin who his main opponent is in these 'elections.' And he wants to make sure that Navalny's voice is not heard. This means that everyone should become Navalny's voice," Volkov said.

A spokesperson for the U.S. State Department welcomed news that Navalny had been located, but said the U.S. remains "deeply concerned for Mr. Navalny's wellbeing and the conditions of his unjust detention."

"The United States strongly condemns Russia's continued malicious targeting of Navalny, and the more than 600 other political prisoners Russia has imprisoned," the spokesperson said. "We will continue to follow their cases closely and advocate for the release of all who are unjustly detained."

Moscow has for years sidelined opposition figures from elections and political life, a clampdown that accelerated after the Kremlin ordered Russian troops into Ukraine in 2022.

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