We feel it's high time these people were made to account for their movements

Victor Barker, father of victim

The BBC's Panorama programme identified and tried to question four men from the Irish Republic, linked by detectives to mobile phones traced to the Omagh area at the time of the blast.

One of those named, Dundalk publican Colm Murphy, 48, has been charged with conspiring to cause an explosion and is awaiting trial in Dublin.

Relatives of 12-year-old James Barker, Samantha McFarland, 17, Lorraine Wilson, 15, and 20-month-old Breda Devine now believe suing those who refuse to answer questions about their movements is the way to get justice.

James' father, Victor, said: "There cannot be peace without justice. We feel it's high time these people were made to account for their movements and civil action is one way to do that.

"It may well be in the course of that action other information might come forward which would help the police pursue their criminal inquiry."

The Daily Mail newspaper has launched a fighting fund to help pay the families' legal costs.

Although relatives plan to take the action in the names of just four families to simplify proceedings, Mr Barker explained that many others were supporting them.

"We chose a small cross-section to highlight the fact that so many children and young people were killed," he said. "This is not a political issue, it is not sectarian, it is a question of justice."