The Nazis ordered the massacres in retaliation for a partisan attack in Rome the day before that killed 33 German soldiers.

Monday's ruling may be the last word on the Priebke affair, which has been marked by drama since Priebke was discovered living in Argentina in 1994.

Extradited to Italy 18 months later to face war crimes charges, Priebke was tried twice on charges of involvement in the Ardeatine Caves massacre.

The verdict of the first trial, which freed him, was annulled after protests from relatives of the victims. In the retrial, he was sentenced to several years in prison. He appealed that verdict, and last March the appeals court toughened the verdict to a life sentence.

Hass was a witness in the first Priebke trial. He was later charged with involvement in the massacre and tried alongside Priebke in the second trial.