Former neofascist militant Marco Toffaloni on Thursday got 30 years in jail for the May 1974 Piazza della Loggia bombing that killed nine people in the northern city of Brescia.
The former far rightist, now 67, and a Swiss citizen, was a minor of 17 at the time of the attack on May 28 1974.
He was not present during the trial at the Brescia minors' court.
The court ruled that he was one of the "material perpetrators" of the atrocity, one of the many episodes of violence during the late 1960s to early 1980s Years of Lead of leftist and rightist political violence.