Authorities in Russia have detained more than 400 people who participated in demonstrations held in memory of Russian opposition leader Alexei Navalny.

Supporters of Navalny were detained in 36 cities including Moscow, St. Petersburg, and Belgorod as they held protests to mark Navalny's death, according to pro-rights group OVD-Info.

The death of the Russian opposition leader has been confirmed by Navalny's allies, but they say the Russian government is refusing to hand over his body.

Bill Browder, the American-born British co-founder of Hermitage Capital Management and an adamant critic of Russian President Vladimir Putin, spoke to DW at the Munich Security Conference (MSC) about the development.

Browder said "Putin killed Alexei Navalny" and the "purpose of this murder is to send a message to anybody in Russia who's even thinking about Vladimir Putin that if you challenge Vladimir Putin, you will be killed."

The apparent targeting of Navalny was "absolutely going to suppress and repress the Russian people, sadly," Browder said.

Circumstances of Navalny's death unknown

The Kremlin has said that the cause of Navalny's death in prison is being investigated.

The prison authorities said the 47-year-old Navalny fell unconscious and died on Friday, after taking a walk in the Arctic penal colony.

While the West has blamed the Russian leadership for Navalny's death, Moscow denies any involvement.

"There are still no results of the forensic investigation, but the West is already drawing its conclusions," Foreign Ministry spokeswoman Maria Zakharova said.

This article was originally published on DW.

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