Leonid Volkov, a close associate of Russian opposition leader Alexei Navalny, who died last month, was attacked with a hammer in the Lithuanian capital Vilnius on Tuesday, Kira Yarmish, Navalny’s former spokeswoman, said.

“Leonid Volkov was just attacked in front of his house. Someone broke the car window and sprayed tear gas in his eyes, after which the assailant began to beat Leonid with a hammer. Leonid is at home now, the police and an ambulance are on their way,” she wrote in X, formerly Twitter.

According to Reuters, Lithuanian police said the man was beaten outside his home and police are investigating.

Leonid Volkov, Navalny’s chief of staff and a leading figure in his movement, announced in 2023 that he had decided to suspend his public activities as head of Navalny’s Anti-Corruption Foundation after asking the European Union to lift sanctions against Mikhail Fridman, one of Russia’s richest men.

Volkov called on the EU to significantly expand the number of Russians under sanctions, as well as facilitate the lifting of sanctions for people who publicly condemned the war in Ukraine and broke with Putin. In particular, he called for the lifting of sanctions against Friedman of Ukrainian origin, calling him a liberal who has always distanced himself from Putin.

Navalny, the most prominent opponent of Kremlin leader Vladimir Putin, died last month at the age of 47 in an Arctic penal colony. His supporters claimed that he was killed.

The Kremlin denies any state involvement in his death.