The Enniskillen bomb in November 1987 was one of the worst atrocities of the Troubles.
An IRA bomb at a Remembrance Day service in the County Fermanagh town killed 11 civilians, including three married couples.
63 people were injured, and a twelfth victim died after being in a coma for 13 years as a result of his injuries.
The massacre sent shockwaves across the world, with the US, UK and Irish government condemning the attack.
There was a huge backlash against the IRA, with Sinn Fein facing electoral reverses in the local area.
But no-one has ever been convicted of carrying out the bombing.
It was thrown back into the spotlight in 2018 after an anonymous letter to the Irish Government claimed MI5 had prior knowledge of the attack, allowing it to happen to turn public opinion against the IRA.
Ciarán Dunbar is joined by former editor of the Impartial Reporter and author of ‘Enniskillen: The Remembrance Sunday Bombing’ Denzil McDaniel to tell the story of the bomb and its aftermath.