Four people are still in custody in Limerick in connection with the Garda investigation into the death of Mr Martin O'Donoghue (36).
Mr O'Donoghue, who was from Brendan Street in the St Mary's Park area of Limerick, died as a result of stab wounds following a row in the city centre early yesterday morning.
A post-mortem was carried out yesterday and gardaí opened a murder investigation.
Two men and two women are being questioned at Henry Street and Mayorstone Garda stations. A spokesman said they were still in custody this afternoon. They may be held for up to 72 hours after their arrest.