The Italian fascist notorious for masterminding the theft of dictator Benito Mussolini's corpse has died, a family member said on Monday.

Domenico Leccisi dug up the dictator's unmarked grave in April 1946. The theft caused a sensation in Italy's fragile postwar democracy and became worldwide news.

Leccisi, who was 88, died at a Milan nursing home on Sunday after a long illness, his daughter-in-law Maria del Canto Merida told Reuters.

Leccisi "was a fascist of the era, and he died a fascist. He never changed his ideas", she said.

"His entire career was lived in the name of Il Duce (the leader)."

Communist partisans killed Mussolini and his mistress in April 1945, as Allied powers were driving his Nazi backers out of Italy at the end of World War Two, and dumped them in Milan's Piazzale Loreto square. The bodies were hung upside down from a petrol station, where a crowd stoned and spat on them.

On the eve of the first anniversary of Italy's liberation from Nazi occupying forces, Leccisi, then a right-wing journalist, and two helpers dug up the corpse from the city's Musocco cemetery and spirited it away.

Leccisi left behind a note that said: "Finally, O Duce, you are with us. We will cover you with roses but the smell of your virtue will overpower those roses."

Authorities discovered Mussolini's remains four months later, hidden at a 15th-century monastery at Pavia south of Milan. Two monks were charged with hiding the body.

In 1957 Mussolini found a final resting place at his birthplace in Predappio, northern Italy, after a campaign led by Leccisi and his party.

Leccisi served as a parliamentary deputy for the neo-fascist Italian Social Movement from 1953 to 1963. He was also a Milan city councillor and wrote an autobiography, "With Mussolini Before and After Piazzale Loreto".