Almost 73 years after a mysterious Nazi unit commander ordered the killing of 44 Poles during World War II, prosecutors believe they finally have their man.

Poland announced Monday it would seek the arrest and extradition of a 98-year-old Minnesota man after prosecutors said they confirmed “100 percent” he was the fiendish Nazi killer who burned villages filled with women and children and murdered civilians in Poland.

The evidence -- gathered in years of investigation into U.S. citizen Michael Karkoc -- showed he was a commander of a unit in the SS-led Ukrainian Self Defense Legion, which is accused of burning villages and killing civilians in Poland, prosecutor Robert Janicki told The Associated Press.

Karkoc's family denied he was involved in any war crimes. "The Associated Press is peddling fake news," Karkoc's son, Andriy, told the Minneapolis StarTribune.

When Karkoc came to the U.S. in 1949, along with his two sons, he said he had performed no military service. He eventually remarried and had four other children.

Prosecutors of the state National Remembrance Institute have asked a regional court in Lublin, Poland, to issue an arrest warrant for Karkoc. If granted, Poland would seek his extradition, as Poland does not allow trial in absentia, Janicki said.

He said the man's age was no obstacle in seeking to bring him before justice.

"He is our suspect as of today," Janicki said.

If convicted of contributing to the killing of civilians in the villages of Chlaniow and Wladyslawin in July 1944, Karkoc could face a prison term for life.

Prosecutors in Germany previously launched their own investigation of Karkoc after stories in 2013 by The Associated Press revealing that he had been a former commander in the SS-led unit that had committed war crimes in Poland.

They never expressed doubts about Karkoc's identity, but shelved their investigation after saying they had received "comprehensive medical documentation" from doctors at the geriatric hospital in the U.S. where he was being treated that led them to conclude he was not fit for trial.

The Associated Press contributed to this report.

