Alleged Omagh bomber Sean Hoey was "fully aware" the bomb planted in the town in August 1998 would result in deaths, his trial heard today.
Prosecutors claimed they had enough DNA and forensic evidence and expert voice analysis to convict him of the outrage and a series of other strikes on civilian, police and British army targets.
Mr Hoey (37) sat impassive in the dock at Belfast Crown Court, flanked by two prison wardens, as Crown QC Gordon Kerr accused him of being at the heart of the worst single atrocity in 30 years of violence in Northern Ireland.
Mr Kerr said: "He was fully aware that the persons concerned were placing explosives and had an active role in the preparation of the devices.
"The evidence will suggest that he contemplated the use of the devices in such a way that injury up to and including death would occur, and agreed to that.
"In the case of Omagh, it will be submitted that those involved in placing a device in a busy public street at a prime shopping time were aware and must have known that an explosion in those circumstances would kill or at least seriously injure those in the vicinity of the explosion.
"It will be submitted that in this case an analysis of the warnings given when compared to other warnings using the same code word suggests that the warnings were not and could not have been meant to be effective.
"In those circumstances the prosecution case is that those responsible at law for the bomb in Omagh should properly be found guilty of murder in relation to the persons who were killed on August 15 1998."
Relatives of some of those killed in the Real IRA attack on the Co Tyrone town were in the public gallery as the trial, which is expected to last for three months, got underway.
Others had gathered 70 miles away in Omagh where a closed circuit video link facility has been set up for the duration of the trial.
They had been frustrated earlier this month when the case was adjourned because senior defence counsel Orlando Pownall was too unwell to proceed. But today the QC assured Judge Mr Justice Weir he was ready to take the non-jury case.
At one stage the names and ages of all those killed at Omagh were read out in the hushed courtroom. They included three generations of the same family - an 18-month-old girl, her mother who was pregnant with twins and a 66-year-old grandmother.
Wearing a beige jacket, striped shirt and jeans, Mr Hoey, of Molly Road, Jonesborough, south Armagh, showed no emotion as the victims were listed.
He denies a total of 58 charges, which the prosecution alleges were part of a violent campaign waged by dissident republicans before and after the Belfast Agreement was signed in April 1998.
PA