On 15 August 1998 a car bomb planted by the Real IRA exploded in a market street in Omagh, County Tyrone, killing 29.
The bombing was the worst paramilitary attack in Northern Ireland's conflict since it began in the 1970s. The dead included nine children and a woman pregnant with twins.
The Real IRA later apologised for the bombing saying it had intended only to hit commercial targets.
Prince Charles and the then First Minister David Trimble were among dignatories to express their sorrow in the days after the bomb.
Thousands gathered in Omagh on the first anniversary of the bombing. It would be seven years before the trial of Sean Hoey began. He was found not guilty of all charges.
Michael Gallagher, who lost his son Aidan in the attack, arrived with family at Belfast Crown Court on 20 December, 2007, to hear the judge's ruling after 10 months' deliberation.
Rita Hoey, the mother of Sean Hoey, said her son had been the victim of a "witch-hunt" and was completely innocent.
Victor Barker, whose son James died in the attack, was critical of the police investigation.