`I was where I am now, sitting at the telephone talking to somebody whose mother was sick in hospital. I heard it and saw the smoke coming up, and I went straight into town. I knew it was a bomb.
"But by the time I got in, most of the bodies had been covered and the last of the injured were being brought to hospital.
"You were so shocked you didn't realise what happened. You were going through the motions of praying with people but you weren't really taking in the awfulness of what had happened. It was only after a day or two you realised . . ."
Father Mullan, curate in the parish of Cappagh, Omagh, recalls the horror of the day when a car bomb turned a Saturday afternoon in the Tyrone market town into a scene of death and destruction. Twenty-nine people died in the blast, including two unborn babies, and hundreds were injured.
Life in Omagh would never be the same again.
Three years on, the town is still trying to come to terms with the sheer awfulness of that day and to, somehow, turn the tragedy into hope for the future. "I think there is just a yearning, a yearning to get through this," Father Mullan says.
"We still bear the scars deep down but there is a yearning for justice, for a new beginning, a yearning for economic and cultural development, a yearning to hold on to the togetherness that was there in the months after the bomb."
The first tentative steps in rebuilding Omagh's future have been made. The business community got together last year and launched "October 2010", a strategy for the town's economic development.
Plans are under way to establish a provincial trauma centre so that the expertise gathered from dealing with trauma can be passed on to people who find themselves in similar situations.
Young people from local schools have formed the Omagh Community Youth Choir which, performing as far away as America, has become a sign of hope for the town. The churches are working out, by means of an ecumenical inter-church forum, how best to play their role in the development of a new Omagh, of a human environment where hurt can find a home.
"We're trying to create an Omagh that people can belong to again - an Omagh, hopefully, in spite of petty vandalism and drugs and all the normal things that go on in every town, to which people can come back into; a community where their history is respected, a place that will give them the sense that life can go on for them though they carry the burden of the past," he says.
These and many other projects are on the boil but it's still early days and the horror of the explosion is not likely to be forgotten easily.
Father Mullan continues: "Everybody says they remember Omagh because it was the centre of a lot of worldwide sympathy at the time. That's been good and not good because you don't know if you should be living up to the image of a place of continuing suffering or a place that should move on.
"The families who suffered, in the main, would like to find out who did it, and justice is very important to them. A lot of others in the community feel we're not getting anywhere anyhow and let's get on with it. There's the tension as to how to be faithful to the dead, how to do justice to the dead while at the same time move on with the living."
Shaping a future is, therefore, a slow process. While Omagh is on the international map as a town which has experienced immense grief, it is by no means an international player in economic terms. It is an ordinary market town to which something very bad has happened and which is now struggling to regain a sense of normality.
"Businesses are struggling, and you sense that in the town," Father Mullan says. "We've rebuilt one of the sides of the streets that were damaged, but business is not good and there are still a lot of people who don't want to come to Omagh because of the memory of it and also because of the innumerable bomb scares . . .
"Once or twice it was the actual police team who were on duty on the day of the bomb that were also on duty when the bomb scare came in. You can imagine the panic," he adds.
A native of Omagh, Father Mullan returned there in 1991, a year after his father died, so he could be close to his ailing mother. In 1993 she also passed away.
As a priest working on the ground, he sees the continuing suffering at first hand. "We are just there with them and they appreciate the love and support of people being at our side. That's all you can do," he says.
During the inquest into the victims' deaths last October, he broke down and cried.
"The worst moment for me was when I heard that the two unborn babies who died could have been delivered. I felt so guilty. I felt guilty because I saw the dead pregnant woman but I didn't think that they could have been saved. There was nothing I could have done anyway." With the inquest over he is beginning to put August 15th, 1998, behind him. It was only then that he began "to come to normal life again. I know people say to me you're looking more relieved and I suppose I am. With the closing of the inquests a whole burden seemed to lift."
It's time to think about the future.
"I think we're searching for our future. We glanced a bit of our future in the love that came to Omagh and now we're learning how to hold on to that and recreate again. We are rebuilding in so many ways - the physical rebuilding and trying to rebuild the spirit. We're not sure what the future is but we hope it will be good and will be a future for everybody."
One thing Father Mullan and the people of Omagh have learned from the experience of recent years is that the future of the town does not rest with one individual, group or church.
"We learned that we are a team. We were there and we are there and always will be there for one another."
This article by Teresa Nerney first appeared in Reality. From Sligo, she is a regular contributor to the magazine.