The spokeswoman of imprisoned Russian dissident Alexei Navalny confirmed his death on Saturday, one day after Russian state media reported the 47-year-old has died.

In a post on X, formerly Twitter, spokeswoman Kira Yarmysh cited Navalny’s mother, who travelled to the prison camp in northern Russia and received the news of her son’s death there.

“Alexey Navalny was murdered. His death occurred on February 16 at 2:17 p.m. local time, according to the official message to Alexey’s mother,” Yarmysh wrote.

According to a report by state news agency TASS, the 47-year-old collapsed on Friday after a walk in his penal colony in the northern Russian region of Yamal and immediately lost consciousness, adding that resuscitation attempts by paramedics were unsuccessful.