Leonid Volkov, a close ally of late Russian opposition leader Alexei Navalny, was admitted to a hospital on Tuesday after being attacked outside his home in Lithuania, local police told AFP.
Volkov, 43, is one of Russia's most prominent opposition figures and was a close confidant of Navalny, working as the late leader's ex-chief of staff and as chairman of his Anti-Corruption Foundation until 2023.
"Leonid Volkov has just been attacked outside his house. Someone broke a car window and sprayed tear gas in his eyes, after which the attacker started hitting Leonid with a hammer," Navalny spokeswoman Kira Yarmysh said on X, formerly Twitter.
Volkov's wife, Anna Biryukova, shared photos of her husband's injuries on social media, including a black eye, a red mark on his forehead and bleeding on his leg that had soaked through his jeans.
Navalny's team later shared a photo of Volkov being carried into an ambulance on a stretcher.
Lithuanian police spokesperson Ramunas Matonis confirmed to AFP that a Russian citizen was assaulted near his home in the capital Vilnius around 10 p.m. local time.
"A lot of police are working at the scene," Matonis said.
A suspect has not been identified and more details about the assault are expected on Wednesday morning, he added.
Police confirmed that Volkov had been admitted into a hospital.
The attack comes almost a month after Navalny's death in an Arctic prison, which Volkov blamed on Russian President Vladimir Putin, and days before elections set to extend the Kremlin chief's stay in power.
The day before he was attacked, Volkov wrote on social media: "Putin killed Navalny. And many others before that."
Lithuania's Foreign Minister Gabrielius Landsbergis condemned Volkov's attack in a social media post.
"News about Leonid's assault are shocking. Relevant authorities are at work. Perpetrators will have to answer for their crime," he said on X.
NATO member Lithuania is home to many Russian exiles and has been a staunch supporter of Ukraine throughout Russia's invasion.
Russian dissidents who have spoken out against the Kremlin often complain of being targeted with threats and attacks.
Volkov told the independent Russian news outlet Meduza hours before he was beaten on Tuesday that he was worried for his safety after Navalny's death.
"The key risk now is that we will all be killed. Why, it's a pretty obvious thing," the outlet quoted him as saying.
Volkov went into exile in 2019 along with several of Navalny allies after authorities launched a criminal probe into the leader's Anti-Corruption Foundation.
Volkov was declared wanted by Russian authorities in 2021 over his role in drumming up mass protests against the Kremlin together with Navalny.
