The trial of the first man ever to face murder charges over the Omagh bombing was delayed today, after the defence barrister fell ill.

The 500lb Real IRA car bomb that tore through the town centre without warning eight years ago, on a Saturday afternoon in mid-summer, represented the single worst atrocity in 30 years of violence in Northern Ireland.

Around 40 relatives of the victims turned up at the Crown Court in Belfast this morning to watch Sean Hoey, 37, from south Armagh, go on trial.

Mr Hoey, an electrician, was flanked by two prison officers as he sat in the dock wearing a corduroy jacket over a green and white striped shirt and denim jeans. One woman burst into tears when she caught her first sight of him.

But instead of the opening of the prosecution case, the relatives saw Orlando Pownall, QC, Mr Hoey's defence counsel, rise to his feet to warn that he was unfit to proceed, and had only flown to Northern Ireland at the last minute to alert the court.

During a tense exchange with the judge, who expressed frustration at the late request to delay one of the biggest murder trials in British legal history, the lawyer said that he hoped blood tests would clear him to begin on September 18. “I am unwell. I appear before you against medical advice,” said Mr Pownall.

Mr Hoey is charged with the murders of each of the 29 people killed in the attack on the small town in Co Tyrone on August 15, 1998. One of the dead was a mother of unborn twins.

He is also charged with a further 32 terrorist and explosive offences - all of which he denies. He has spent three years in prison on remand since his arrest on suspicion of being the bombmaker behind a string of explosions in the summer of 1998, culminating in the devastating attack on Omagh.

Expert voice analysis and DNA evidence are expected to be central to the prosecution case.

With no jury to be sworn in because of the laws governing terrorist trials in Northern Ireland, the case against Mr Hoey, of Molly Road, Jonesborough, Co Armagh, will be heard by Mr Justice Reg Weir. Once it gets under way the case is expected to last for three months.

Outside the court relatives said they were devastated by the new delay.

Michael Gallagher, whose son Aiden was among the victims, said: "There is utter disbelief. We came here having psyched ourselves up for this day only to find there’s been a false start. It hasn’t been easy for the relatives and this just adds to the difficulties we all face."

Whenever the trial finally gets going a painful ordeal lies ahead. Stanley McCombe, whose wife, Ann, 48, was killed in the blast, said: "It’s a day I have been waiting for, but yet I’m not looking forward to going near the court. It’s going to be tough watching somebody who is accused of being one of the instigators.

"But we have come through hell and high water before, and if this is going to give us a little bit of peace then so be it."

The decision to prosecute followed a marathon police investigation which has been mired in controversy.

A report by Nuala O’Loan, the Police Ombudsman, was heavily critical of the initial police inquiry and the then Chief Constable Sir Ronnie Flanagan. She found that warnings from two informants in the days before Omagh that a terrorist attack was planned for Northern Ireland were not properly followed up.

The families, meanwhile, have continued to demand justice for their loved ones.

WIth most of those living in Omagh likely to find it impossible to make the daily three-hour round trip for a trial that could last for months, requests have been made to set up a videolink system in the town for the duration of court proceedings.

Mr McCombe insisted everything possible should be done to facilitate the relatives. "The facilities are there, so why not? Anything else would mean at least a 12-hour day, with us leaving early in the morning."

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