A ceremony has taken place to mark the 50th anniversary of the Castleblayney bombing.
One man, 56-year-old Patrick 'Packie' Mone, was killed in the blast.
A no-warning car bomb exploded outside the Three Star Inn on Main Street at 8.20pm on 7 March 1976.
The bombing also left 17 other people injured and caused extensive damage to the surrounding buildings in the Co Monaghan town.
It is believed that the intended target was the Dublin-Derry bus that was due to arrive at the location at 8.20pm, but which was two minutes late after it was held up by a garda checkpoint.
Mr Mone was a married man and worked as a bicycle mechanic. No one has ever been charged or convicted in relation to this attack.
A nephew of Mr Mone laid a wreath at the monument to his uncle during the ceremony.
Tommy Mone said the bombing and the death of his uncle had devastated his family.
He was living in England at the time when he heard the news. He said he was not expecting that his uncle would have been in Castleblayney that night, but that he was dropping a woman in to catch a bus.
"He moved the car three times. The last time it was right behind. He got out to see which way the bus was coming, from Keady or Monaghan. He stood behind the car with the bomb in it, and it went off".
Mr Mone said the family is still waiting for justice.
"We've asked the British and Irish governments for the papers, but nothing has ever come out, we got nowhere, no justice at all. We're still living 50 years on, not a thing."
An eye-witness to the bombing attended today's memorial event.
Benny Maguire from near Rosslea in Co Fermanagh had been giving a man a lift to Castleblayney that night.
Mr Maguire said he was about 50 yards from where the bomb went off.
"All I can recall is the flash and the noise, and the debris coming down".
Mr Maguire said that the back door and boot of the car were blown open, but he was lucky not to be injured.
"It was terrifying. There was a lot of bombs that went off in Northern Ireland, but I never was close to any of them. I've never forgotten it. I can still see in my mind's eye, the car being hurtled across the street there and all the cables came down".
The Cathaoirleach of Monaghan County Council PJ O'Hanlon and the Cathaoirleach of the Carrickmacross Castleblayney Municipal District Paul Gibbons also laid a wreath during the ceremony, which was also attended by local Sinn Féin TD Matt Carthy.
Margaret Urwin from Justice for the Forgotten also addressed those who gathered for today's memorial.
The bombing has been linked to the UVF unit known as the Glenanne Gang, which is also implicated in the Dublin-Monaghan bombings, the Miami Showband massacre, and the Belturbet, Dundalk and Dublin Airport bombings.
Families who lost loved ones in the series of attacks linked to the so-called Glenanne Gang are currently awaiting the full publication of Operation Denton.
This was launched in March 2020 after a judge ruled there should be an independent review into the group's activities and allegations of collusion.
The group is said to have consisted of members of the loyalist paramilitary group, the Ulster Volunteer Force, and members of the RUC and Ulster Defence Regiment.
It has been linked to 127 sectarian murders in the 1970s and 1980s.
