Former U.N. Secretary-General Kurt Waldheim, who was elected Austrian president despite an international scandal about his secretive World War II military service, died Thursday, Austrian media reported. He was 88.

Waldheim, who was hospitalized in Vienna late last month with a fever-causing infection, died of heart failure, state broadcaster ORF reported, citing his family. Waldheim's tenure as U.N. chief from 1972-82 and his election as president in 1986 were overshadowed by revelations that he belonged to a German army unit that committed atrocities in the Balkans during World War II.