Belfast, Northern Ireland (CNN) -- He was a 21-year-old with the mind of a child who was kidnapped, killed, and buried in secret nearly four decades ago.
Friday, Peter Wilson was finally laid to rest in his native west Belfast. Authorities discovered his remains last month and identified them this week.
Wilson, who had special needs, went missing from his home in August 1973 and became one of Northern Ireland's so-called Disappeared -- 16 people who vanished between 1972 and 1985, when the province was engulfed in violence between pro-Irish republicans and pro-British unionists.
During Friday's homily at Holy Cross Catholic Church, the Rev. Gary Donegan called the killing "senseless and cruel." Mourners were told that, although Wilson was 21, he had the intellect of a child of 13 or 14.
Donegan described Wilson as "an innocent" and "a boy in a man's body who would remain forever young."
Wilson was the ninth member of the Disappeared to be recovered; seven are still missing.
The Provisional Irish Republican Army admitted responsibility for 11 of the disappearances, while the Irish National Liberation Army -- also a republican group -- said it was responsible for another, according to the commission searching for the bodies.
Four of the deaths, including Wilson's, remain unexplained, though investigators believe he was abducted and killed by the Provisional Irish Republican Army.
Wilson's remains were recovered from a beach in County Antrim on November 2 after a tip believed to have come from within the republican movement.
The excavation that led to the recovery of his remains was the first search for a Disappeared victim in Northern Ireland. The rest have been in the Republic of Ireland.
In October, investigators found the remains of another of the Disappeared, Gerry Evans, in Ireland.
Evans, from Crossmaglen in south Armagh, Northern Ireland, was 24 when he vanished in March 1979 in County Monaghan, Ireland.
The Provisional Irish Republican Army is suspected of abducting, murdering and secretly burying him.
His remains were recovered last month in marshy ground at Carrickrobin, only days after officials had given up hope of finding a body following a 16-month search.