The leader of the Real IRA has been jailed for 20 years after being found guilty in a landmark trial in the Republic of Ireland of directing terrorism.
Michael McKevitt's sentences will run concurrently
Michael McKevitt, 53, from Blackrock in County Louth was found guilty of directing terrorism and membership of an illegal organisation at the Special Criminal Court in Dublin on Wednesday.
It is the first time the charge of directing terrorism has been brought before a court in the Irish Republic.
The offence was one of a range of measures introduced by the Irish Government in the wake of the Omagh bombing.
He was also sentenced to six years for membership of an illegal organisation.
The sentences are to run concurrently.
McKevitt appeared in court after the sentence had been handed down to seek leave to appeal, but this was refused.
During the sentencing Mr Justice Richard Johnson reminded the court that the charges did not cover the period of the Omagh bombing.
He said: "The court must not allow itself to seek revenge for the victims of that atrocity and does not seek to do so."
Although the offences date after the Omagh bombing, Mr Justice Johnson said: "The court is satisfied that the offences were planned and premeditated and contemplated to do serious harm to people and property.
"The accused played a leading role in the organisation which he directed and induced others to join."
As McKevitt was the first person in the Republic of Ireland to be convicted of the terrorism charge, there was no precedent for the length of jail term for such an offence.
McKevitt has already served two and a half years on remand.
Twenty-nine men, women and children died and hundreds were injured when the Real IRA detonated a car bomb in Omagh on 15 August 1998.
However, the judges stressed on Wednesday that the offences McKevitt was convicted of dated from after the atrocity.
McKevitt, a businessman from Blackrock in County Louth, had denied the charges.
Speaking after the sentence was handed down, Stanley McCombe, whose wife, Anne, was among those killed at Omagh, said the sentence "does ease the pain a bit" but not much.
He told BBC News 24: "We've had our life sentences.There's no remission for us".
In their judgement, the three justices said the chief prosecution witness, FBI agent David Rupert, was a truthful witness and his credibility had not been impugned.
The sentencing was delivered at the Special Criminal Court
Detective Chief Garda Superintendent Martin Callinan said the verdict was a "significant result".
The trial came to a speedy end last month after McKevitt sacked his legal team, denouncing the proceedings as a "political show trial".
The following day he refused to come into the courtroom, saying he wished to take no further part in the trial.
The Real IRA was formed after a split within the mainstream IRA. The dissident group is opposed to the Northern Ireland peace process.