Seven people were wounded in knife attacks in the first four hours of 2006.
A man in his 20s was in a critical condition in the Mater hospital, Dublin last night after being stabbed in the north inner city following New Year's Eve celebrations.
The man, who was a guest at the Jury's Croke Park Hotel on Jones's Road, received a single stab wound to the upper chest following a brawl.
It is understood the stabbing took place near the hotel, to which the man made his way back before collapsing.
Gardaí said that when they arrived at the scene shortly after 4am they found the man lying on the ground at the hotel. He remained in intensive care last night.
In Co Limerick, a fight between a group of young men left at least five people with stabs, gashes and other wounds.
It is understood the row broke out shortly after 2.30am as the group was on its way to a house party on Brenknock Court Avenue, a new housing estate in Newcastlewest.
Gardaí were alerted after a sergeant on patrol noticed a man bleeding heavily on St Mary's Road. A call was then received from the house where four more men in their early 20s were also injured.
All five were taken to the Mid Western Regional Hospital but two of them had been discharged by early yesterday afternoon.
While one of the victims is understood to have lost a lot of blood, none of the injuries was said to be life-threatening.
Gardaí said their inquiries were being hampered by the fact that no complaint had been made by the men, all of whom were Lithuanian.
No motive has yet been identified and it was still unclear yesterday whether the men had been stabbed with knives, broken glass, or a combination of the two.
"No implements have been recovered yet and we are still waiting to interview the victims. We believe at this stage that this seems to have been a row which broke out between a number of non-nationals from Lithuania who are living in the town," said a Garda spokesman.
In Co Antrim, a 36-year-old man was stabbed in the back after a fight on a garage forecourt at North Road, Ballymena at about 2am.
Two men were subsequently arrested but police are continuing to appeal for witnesses.