The Austrian Independent said Asner, 98, who was suspected of deporting hundreds of Jews, Serbs and Roma from Croatia during World War II, changed his name to Georg Aschner when he fled to Austria in 1945, the Austrian Independent reported.
The Independent said Asner lived in Carinthian until his death.
Asner was said to be suffering from dementia in his later years, making prosecution for war crimes difficult. A case against him was opened in 2004.
"His decisive role in the killing of hundreds of Jewish people, Serbians and Roma in the Slavonian city of Prozega is evident," Efraim Zuroff, the director of the Simon Wiesenthal Center's office in Jerusalem, told the newspaper.