Alexei Navalny’s lawyer has confirmed that the opposition leader is “seriously ill” after reports emerged that he had been transferred to a prison sick ward for a respiratory illness and had been tested for coronavirus. The Kremlin critic said in a note published on Monday that he was coughing and had a temperature of 38.1C (100.6F). Several prisoners from his ward had already been treated in hospital for tuberculosis, Navalny wrote. Hours later, the pro-Kremlin newspaper Izvestia reported he had been moved to a sick ward and tested for coronavirus, among other diseases. On Tuesday, Russian police arrested several Navalny supporters who had travelled to the prison 60 miles east of Moscow to petition for him to receive proper medical care. Anastasia Vasilyeva, the head of the Russian Doctors’ Alliance, along with three other members of the renegade medical union were arrested. Reporters for CNN and for Belsat, a Russian-language television channel based in Poland, were also briefly detained. “We are coming here today to offer help,” Vasilyeva told journalists before her arrest. “There’s no war here. Let’s settle this problem like people.” A lawyer for Navalny said that a member of his legal team had seen the opposition leader on Tuesday and that he was “in rather bad condition”. Navalny declared a hunger strike last week because he had been denied a visit from a personal doctor for growing numbness and pain in his back and legs that had made it difficult for him to walk. “He has lost a lot of weight, plus he has a strong cough and a temperature of 38.1C,” Olga Mikhailova, the lawyer, said on the Echo of Moscow radio station. “This man is seriously ill. It’s a complete outrage that the IK-2 [prison] has driven him to this condition.” In a letter published on Monday, Navalny wrote that three inmates in his ward had been taken to hospital recently with tuberculosis. He joked darkly that if he had contracted the disease, it could distract him from “the pain in my back and numbness in my legs”. There has not been official confirmation of Navalny’s medical treatment, although a lawyer speculated on Monday that the sick ward was probably in the IK-2 prison colony, 60 miles east of Moscow, where he is being held. The prison is notoriously strict and said to specialise in isolating prisoners from the outside world. Navalny’s wife, Yulia, on Tuesday published a letter sent to her from the prison warden who said that he could not send Navalny to hospital because he did not have his passport. In a statement posted online, she also claimed that the warden had taunted her husband by grilling a chicken and handing out sweets to his fellow inmates while the opposition leader has maintained his hunger strike. Navalny is serving a two-and-a-half year prison term on embezzlement charges that he has said is retribution for his political opposition to Vladimir Putin. Navalny survived a poisoning attempt that he traced back to Russia’s FSB last year. He was arrested in January when he returned to Russia from Germany, where he had been treated for poisoning with a novichok-type nerve agent. Navalny has compared the prison colony to a “concentration camp” and complained of sleep deprivation and other psychological pressure. Last week, a pro-Kremlin activist who had been jailed on spying charges in the US visited him in the prison, telling him that he had exaggerated the poor conditions there. “I’m tired of the complaining. He is in one of the best penal colonies in Russia,” Maria Butina, who now works for the state-funded television station RT, posted on social media. She visited the prison with a camera crew in tow. Navalny complained about the visit in a note posted to his Telegram channel: “Instead of a doctor, today the miserable RT television propagandist [Maria] Butina came along with video cameras,” he said. Amnesty International’s secretary general, Agnès Callamard, said on Monday that she had written to Vladimir Putin about the “arbitrary arrest and deteriorating health condition” of Navalny. Later on Tuesday, Navalny said he had been visited by doctors representing the Vladimir region who said they would not allow him to meet with someone sent from Moscow, a decision that he said violated the law.