Alexei Navalny's mother was told on Saturday that Russia's most prominent opposition leader had been struck down by «sudden death syndrome» and that his body would not be handed over to the family until an investigation was completed, his team said.
Navalny, a 47-year-old former lawyer, fell unconscious and died on Friday after a walk at the «Polar Wolf» penal colony in Kharp, about 1,900 km (1,200 miles) northeast of Moscow, where he was serving a three-decade sentence, the prison service said.
Western leaders led by U.S. President Joe Biden paid tribute to Navalny's courage and, without citing evidence, accused President Vladimir Putin of being responsible for the death. Britain said there would be consequences for Russia.
The Kremlin said the West's reaction was unacceptable and «absolutely rabid». Putin has yet to comment on Navalny's death.
Navalny's 69-year-old mother, Lyudmila, braved Arctic temperatures of minus 30 degrees Celsius (minus 22 degrees Fahrenheit) on Saturday to visit the penal colony where her son perished.
She was given an official death notice stating the time of death as 2:17 p.m. local time (0917 GMT) on Feb. 16, Navalny's spokeswoman, Kira Yarmysh, told Reuters.
«When Alexei's lawyer and mother arrived at the colony this morning, they were told that the cause of Navalny's death was sudden death syndrome,» Ivan Zhdanov, who directs Navalny's Anti-Corruption Foundation, said on social media platform X.
«Sudden death syndrome»