Rory Finnis was only 21 when he was killed in 1991 by the Irish Republican Army.
Accused of informing the Northern Ireland government of the paramilitary group's activities, the Londonderry man was shot in the head. His hands had been tied behind his back, his eyes taped closed.
Details of his death, along with many others, have been revealed in archives newly opened by the Public Records Office of Northern Ireland.
The files concern the violent period known as "The Troubles," which centred on whether Northern Ireland would be part of the United Kingdom, as it is today, or join Ireland.
The conflict, lasting from roughly 1968 to 1998, claimed some 3,700 lives and was ended by a power-sharing system called Good Friday Agreement.
It has long been known that alleged agents or informers were often killed by the Provisional IRA, but the newly declassified documents include fresh details about those killed between 1978 and 1994.
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During "The Troubles," the government did not usually confirm whether those killed were informers.
"In a number of cases, persons murdered by the IRA have not been informers," the official record, found in the archives, says.
"Furthermore, in other cases alleged informers have had to leave Northern Ireland at a moment's notice and start a new life elsewhere, knowing that they can never return to their homes without facing the prospect of torture and murder, possibly having to cut off their links with close family members in order to avoid the risk of their new location being revealed."
"This usually means torture, followed by a forced confession and murder. The corpse will then be found in a ditch, often many miles from the point of abduction."