Vladimir Katriuk's lawyer said his client had been ill for a long time before his recent death at the age of 93.
"I think it was last Friday," Orest Rudzik said from Oakville, Ont. "It was a stroke or something do with a stroke."
Katriuk, a native of Ukraine who had been an avid beekeeper for years in Ormstown, Que., was at the heart of allegations he participated in a village massacre in 1943 in what is now known as Belarus.
An official with the Russian Embassy said Katriuk's death makes it impossible, "unfortunately," for him to face justice.
"Sadly, the Canadian government ignored numerous appeals by Canadian Jewish organizations and efforts by the Russian authorities to ensure that justice be served, allowing Vladimir Katriuk to retain citizenship of Canada while peacefully residing in this country," press secretary Kirill Kalinin said in an email sent to The Canadian Press.
"Employing legal or politically motivated loopholes to evade from trying or extraditing Nazi war criminals is totally unacceptable."
Russia's intervention in Ukraine has led to Canada all but severing relations with Russian President Vladimir Putin as well as imposing a slew of sanctions against individuals and entities in both countries.
The Federal Court ruled in 1999 that Katriuk lied about his voluntary service for German authorities during the war in order to obtain Canadian citizenship.
The court concluded Katriuk had been a member of a Ukrainian battalion implicated in numerous atrocities in Ukraine — including the deaths of thousands of Jews in Byelorussia between 1941 and 1944.
But in 2007 the Canadian government overturned an earlier decision to revoke Katriuk’s citizenship, due to a lack of evidence.
A study three years ago alleged Katriuk was a key participant in a massacre in Khatyn during the Second World War.
The article said a man with Katriuk's name lay in wait in March 1943 outside a barn that had been set ablaze, operating a machine-gun and firing on civilians as they tried to flee the burning building.
The same document said the man took a watch, bracelet and gun from the body of a woman found nearby.
"One witness stated that Volodymyr Katriuk was a particularly active participant in the atrocity: he reportedly lay behind the stationary machine-gun, firing rounds on anyone attempting to escape the flames," said the article, authored by Lund University historian Per Anders Rudling.
Rudling, whose research was published in the spring 2012 issue of Holocaust Genocide Studies, attributed these details to KGB interrogations released for the first time in 2008.
News of Katriuk's death emerged just several hours after the Centre for Israel and Jewish Affairs said Ottawa should take the necessary steps to ensure he be held accountable if he were found guilty of war crimes committed in collaboration with the Nazis.
A spokesman for the centre had nothing to add when informed of Katriuk's death.
Asked to comment on the death, a spokeswoman for Federal Justice Minister Peter MacKay said in an email that war criminals are not welcome in Canada.
"Those who have been involved in war crimes will find no haven in Canada — they will be located and they will face the consequences," said Mary Ann Dewey-Plante, MacKay's communications director.
In a 2012 interview with The Canadian Press, Katriuk repeatedly refused to discuss anything about himself — other than his passion for honey bees.
"I have nothing to say," he said at the time of the accusations.
"When we talk about bees, that's different. When we talk about my own affairs, that's something else. I'm sorry."
Asked how he felt about having his name on the list of worst surviving Nazis (he was No. 4 on the most-wanted list in 2012), Katriuk paused. He reached into a box and pulled out a piece of a beehive: "You see?" he said. "Here they have started to make the royal cell (for a queen bee)."
Pressed further about the allegations, he replied: "Let people talk."
Rudzik, who was Katriuk's lawyer for more than 30 years, said his client had lived through some hard times.
"He would get calls in the middle of the night from nasty people," he said.
"He was ailing, he had heart problems...and he would call me and I would basically do a hand-holding exercise, you know, tell him, 'not to worry, nothing in it, we've been through all this, been there, done that, so please, please relax.'"
Rudzik said he was informed of the death by a relative of Katriuk's and that he last spoke to his client a few months ago.
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