Karkoc refused to discuss his wartime past at his home in Minneapolis, and repeated efforts to set up an interview, using his son as an intermediary, were unsuccessful.
Efraim Zuroff, the lead Nazi hunter at the Simon Wiesenthal Center in Jerusalem, said that based on his decades of experience pursuing Nazi war criminals, he expects that the evidence showing Karkoc lied to American officials and that his unit carried out atrocities is strong enough for deportation and war-crimes prosecution in Germany or Poland.
"In America this is a relatively easy case: If he was the commander of a unit that carried out atrocities, that's a no brainer," Zuroff said. "Even in Germany ... if the guy was the commander of the unit, then even if they can't show he personally pulled the trigger, he bears responsibility."
Former German army officer Josef Scheungraber — a lieutenant like Karkoc — was convicted in Germany in 2009 on charges of murder based on circumstantial evidence that put him on the scene of a Nazi wartime massacre in Italy as the ranking officer.
German prosecutors are obligated to open an investigation if there is enough "initial suspicion" of possible involvement in war crimes, said Thomas Walther, a former prosecutor with the special German office that investigates Nazi war crimes.
The current deputy head of that office, Thomas Will, said there is no indication that Karkoc had ever been investigated by Germany. Based on the AP's evidence, he said he is now interested in gathering information that could possibly result in prosecution.
Prosecution in Poland may also be a possibility because most of the unit's alleged crimes were against Poles on Polish territory. But Karkoc would be unlikely to be tried in his native Ukraine, where such men are today largely seen as national heroes who fought for the country against the Soviet Union.