The widow of Russian opposition leader Alexei Navalny has vowed to press on with her husband's fight for a free Russia and called on supporters to battle President Vladimir Putin with greater fury than ever.
Navalny's death robs Russia's disparate opposition of its most charismatic and courageous leader as Putin prepares for an election that will keep him in power until at least 2030.
In a nine-minute video message laced with rage, Yulia Navalnaya said Putin had killed her husband and in doing so had robbed her of a husband and her two children of a father.
But she said the only answer to such a crime was to continue her late husband's fight for a free and prosperous Russia.
Russians, she said, wanted to live differently, even if there appeared little hope.
"I want to live in a free Russia, I want to build a free Russia," Navalnaya said in the video message titled "I will continue the work of Alexei Navalny".
"I urge you to stand next to me," she said.
"I ask you to share the rage with me. Rage, anger, hatred towards those who dared to kill our future."
Navalnaya accused the Russian authorities of hiding Navalny's corpse and of waiting for traces of the Novichok nerve agent to disappear from his body.
"Vladimir Putin killed my husband," Navalnaya said.
"By killing Alexei, Putin killed half of me - half of my heart and half of my soul.
"But I still have the other half, and it tells me that I have no right to give up. I will continue the work of Alexei Navalny, continue to fight for our country."
The Kremlin has denied involvement in his death and says Western claims that Putin was responsible for the death are "obnoxious and unacceptable".
Putin has made no public comment, but has warned of a strong response if foreign powers try to meddle in Russia's election.
Navalny, 47, fell unconscious and died suddenly on Friday after a walk at the "Polar Wolf" penal colony in the Arctic where he was serving a three-decade sentence, the prison service said on Friday.
The West and Navalny's supporters have dismissed the service's statement about his death, which has further deepened the schism between Moscow and the West caused by the Ukraine war.
The Kremlin said on Monday the investigation into his death was ongoing, while Russian investigators told Navalny's mother and lawyers his cause of death was yet to be determined.
Navalnaya, 47, always supported her husband in his battles with the Russian authorities, attending his many court appearances, standing beside him at rallies and waiting for release from many prison terms.
"The main thing that we can do for Alexei and for ourselves is to keep fighting. More, more desperate, fiercer than before," she said in her video message.
Navalny rose to prominence more than a decade ago by documenting and poking fun at what he said was the vast corruption and opulence of the "crooks and thieves" running Putin's Russia.
"We know exactly why Putin killed Alexei three days ago," Navalnaya said.
"We will tell you about it soon. We will definitely find out who exactly carried out this crime and how exactly.
"We will name the names and show the faces."
Navalny had been incarcerated at the IK-3 penal colony north of the Arctic Circle located in Kharp in the Yamalо-Nenets region about 1900km northeast of Moscow.
His death came just as Russian forces made their biggest advance in the Ukraine war since May 2023 and as the West debates how much more support to give to Kyiv.
US President Joe Biden blamed Putin for Navalny's death and warned there could be consequences.
However, it is unclear what more the West can do after imposing on Russia what it says are already the toughest sanctions ever imposed on a major economy over the Ukraine war.
