Prospero Gallinari, who as a member of the Italian terrorist group the Red Brigades was convicted in the kidnapping and assassination in 1978 of Aldo Moro, the Italian prime minister, died Monday after collapsing at his home in Reggio Emilia, in northern Italy. He was 62. He was long believed to have been the gunman in the killing until a comrade took responsibility.

Mr. Gallinari had a history of heart trouble, Italian newspapers said, citing police reports confirming his death.

The Red Brigades, a vicious and idiosyncratic Marxist-Leninist paramilitary organization, engaged in robberies, assaults and assassinations in the 1970s as part of a campaign to foment leftist revolution in Italy. The group’s most notorious act was kidnapping Mr. Moro in March 1978. It held him for 55 days and then shot him to death. Mr. Moro’s body was found in a car trunk on May 9, 1978, the same day he was murdered....