Canada's Federal Court on Thursday declined to review a decision to revoke the citizenship of a Ukrainian immigrant accused of having links to a Nazi SS killing squad during World War II.

In a statement, the court said the Canadian government's finding that Helmut Oberlander, now aged 94, had lied about his wartime activities when he arrived in Canada with his wife in 1954 was "justifiable," paving the way to his deportation.

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Canadian court documents allege Oberlander was a member of Einsatzkommando 10a (Ek10a), a Nazi mobile killing squad that systematically executed thousands of people in the former Soviet Union after the German invasion.

When Oberlander landed in Canada, he made no mention of his membership in Ek10a, where he served as an interpreter and an auxiliary, the court said.

The judgment said if Oberlander had revealed this information there is "no doubt" it "would have resulted in the rejection of his citizenship application."

Aware of atrocities

The court's decision upholds the government's conclusion that Oberlander "voluntarily made a knowing and significant contribution to the crimes and criminal purpose of this SS killing squad."

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Judge Michael Phelan found that while no evidence "indicated the applicant directly participated in the atrocities committed by Ek10a … he was aware that these atrocities were being committed."

An estimated 6 million Jews were killed during the Nazi Holocaust carried out under Hitler.

Oberlander, who was born to a family of German ethnicity in Ukraine, became a Canadian citizen in 1960, has maintained that he was forced to join the unit because he spoke both Russian and German and that he only acted as an interpreter.

The court's ruling said that during his time in Canada, Oberlander "is reputed to have made a significant contribution to the local community."

"Oberlander's life since arriving in Canada has been beyond reproach," the ruling said. "He is in his 90s with significant health issues."

It is the fourth time Canada has revoked Oberlander's citizenship, in a saga that has been ongoing since Oberlander's first notice of revocation in 1995. There is a possibility he will appeal the latest ruling.