The Rev. Giuseppe Puglisi is the first victim of organized crime to be declared a martyr, the BBC reported Saturday.
A cardinal representing Pope Francis, 40 bishops and government ministers were present at the ceremony in Palermo, which is the next-to-last step in canonization.
Puglisi was born in Palermo and ordained a priest at age 22. He became a target of the Mafia after he denounced crime in his parish and alleged there was collusion between politicians and Mafia figures.
He was killed on his 56th birthday. Six men are serving life sentences for his murder.