Russian opposition leader Alexei Navalny is "seriously ill" at the penal colony where he’s been locked up and was recently transferred to the prison’s sick ward to be treated for a respiratory illness, reports said Tuesday. 

The longtime Vladimir Putin critic, who’d already been struggling with his health, said in a Monday note that he was coughing and had a fever of 100.6F, the Guardian reported

Navalny has reportedly been tested for COVID-19 but it’s not clear if the results have come back or if he tested positive.

However, several prisoners from his ward have previously been treated for tuberculosis, the oppositionist said. 

MOSCOW COURT REJECTS NAVALNY’S APPEAL 

Olga Mikhailova, a lawyer for Navalny, told the Echo of Moscow radio station a member of Navalny’s legal team visited him on Tuesday and he was "in rather bad condition." 

"He has lost a lot of weight, plus he has a strong cough and a temperature of [100.6F]," Mikhailova said. 

"This man is seriously ill. It’s a complete outrage that the IK-2 [prison] has driven him to this condition."

Navalny, 44, is serving a two-and-a-half-year sentence on embezzlement charges that human rights advocates have called trumped up and politically motivated and a result of the lawyer’s attacks on Putin. 

He was arrested in January after returning from Germany, where he was twice poisoned with a Soviet-era nerve agent.

Last week, Navalny declared a hunger strike when prison officials refused to let him see a personal doctor for help treating pain and numbness in his back and legs that’s made it difficult for him to walk. 

He has previously described the prison as a "genuine concentration camp." 

On Tuesday, several supporters who traveled to the prison to protest the lack of medical care were arrested by Russian police, including Anastasia Vasilyeva, head of the Russian Doctors’ Alliance, and three other members of the group. 

Reporters from CNN and Belsat, a Polish television station, were also detained, the Guardian reported. 

"We are coming here today to offer help," Vasilyeva told reporters before she was cuffed. "There’s no war here. Let’s settle this problem like people."

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Navalny’s wife, Yulia, published a letter Tuesday sent from the prison’s warden that explained her husband couldn’t be sent to a hospital because he didn’t have his passport. 

She further claimed the warden taunted her husband by grilling a chicken in front of him, and handing out sweets to fellow inmates, while Navalny maintained his hunger strike. 

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