The story of the Omagh bomb is “entering a new phase” 25 years on, with a public inquiry on the horizon, the father of one of the victims has said.

Michael Gallagher, whose son Aiden was among the 29 killed in the dissident republican attack on August 15 1998, said he feels they are in a better place.

Earlier this year, Northern Ireland Secretary Chris Heaton-Harris announced that an independent statutory inquiry will be launched to look at the preventability of the blast which devastated the Co Tyrone town.

It came after a High Court judge in Belfast recommended in 2021 that the UK Government should carry out a human rights-compliant investigation into alleged security failures in the lead-up to the attack.

Senior Scottish judge Lord Turnbull has been appointed chairman of the inquiry.

Mr Gallagher stressed that the people responsible for the bomb were those who planned, prepared and delivered the device to Omagh from the Republic of Ireland.

He also made an appeal for anyone who has information that could help the inquiry answer its questions to come forward and speak with officials.

“For the past 23 years, we’ve been campaigning for a public inquiry,” he said.

“That campaign is now over … there is a huge weight lifted off my shoulders, because we don’t need to go around meeting politicians and begging for their support and meeting government ministers.

“We are, on this anniversary, where we want to be, on the cusp of starting the public inquiry, and that will drive the agenda from here on forward.

“And I would encourage everyone, and anyone who has even the slightest piece of information, who can add a piece to the jigsaw, no matter how insignificant they feel it is, I would ask them to engage with the public inquiry.

“People may realise ‘Hold on a minute, I have something to say about that. I was there. I’ve seen this, I’ve done this’, or ‘These people have got it wrong, this is the way it was’.

“I welcome that. I think it’s very important that everybody has their say regardless of whether I agree or disagree with them. This tribunal will be a tribunal of fact, it will not be of my opinion, my thoughts, my views.

“What really matters is fact and that’s the only way you can move forward.”

Mr Gallagher met Ireland’s deputy premier, Micheal Martin, and justice minister Helen McEntee in Dublin in June.

He said the ministers did not commit to hold an Irish public inquiry into the bomb, but are considering how they will contribute to the UK inquiry.

Mr Gallagher said he hopes the inquiry may be able to start by the end of this year or early next year.

“I have no complaints about how the Secretary of State, the Northern Ireland Office and Lord Turnbull himself are progressing,” he said.

“By its nature, it takes time. We’re certainly happy with the progress. I believe that Lord Turnbull is well focused, and he will concentrate on the issues that we need addressed.

“If we’re lucky it might start at the end of this year, but, apart from the administration, there is a huge volume of information to be read by all concerned, legal teams representing the families, the inquiry and others who get representation.”