A man convicted of IRA membership is on hunger strike in a Portlaoise prison this week, the Irish Special Criminal Court was told on Tuesday.

Barry O'Brien, 38, a father of three from Dundalk, County Louth, was convicted in 2010 of IRA membership - an offense in Ireland.

The court was scheduled to sentence O'Brien on Tuesday, but this was halted when the prosecuting counsel Gerard Clarke told the court that O'Brien was not present.

Clarke said he had received a medical report that said that O'Brien was not well enough to attend the court sentencing. "I am told he is apparently on hunger strike," Clarke announced.

Justice Paul Butler, the presiding judge, observed that at a recent court appearance O'Brien had looked poorly. The court then remanded O’ Brien until February 15 for sentencing.

During O'Brien's three-day trial in 2010, chief superintendent Patrick Magee said in evidence that he strongly believed O'Brien was an IRA member.

Irish police force forensic witnesses also told the court they found O'Brien's fingerprints on items seized from a car in Dublin in 2003, in which firearms were also discovered.