Three people were still being questioned by gardaí in Galway last night in relation to the discovery last month of a man's body in a city fishmonger's freezing unit.
The three, a man and two women, were arrested in several parts of the city and suburbs just after 7am yesterday.
A 43-year-old man was arrested in the Knocknacarra area under section 4 of the Criminal Justice Act, and taken to Mill Street Garda station for questioning.
His period of detention, at six hours initially, was extended for a further six hours at lunchtime and a further 12 hours just after 7pm last night.
Two women, one in her 20s and the other in her 40s, were arrested under section 30 of the Offences Against the State Act, which allows for an initial 24-hour period of detention.
The younger woman, who was arrested in Ballybane, was also taken to Mill Street, while the older woman was taken to Loughrea Garda station.
The body of Patrick McCormack (52) was found by the owner of a fishmonger's shop in Henry Street, Galway, on June 13th. A postmortem in Dublin was delayed until the body could thaw.
The postmortem results showed that he had died of head injuries and that he could have been killed up to five years ago. His hands were tied when he was found in the fish box at the back of the freezer unit.
Gardaí in Galway initiated a murder investigation and have been liaising with the National Bureau of Criminal Investigations.
Mr McCormack, from Malahide Road and Foley Street in Dublin, was reported missing by his family in July 2002.
He had convictions for robbery and firearm possession and had been questioned by gardaí in the late 1990s on suspicion of involvement in drugs. His abandoned vehicle was discovered in Shannon in October 2003.
Gardaí at first refused to rule out the possibility that he may have moved to Spain and had staged his own disappearance in a bid to escape Garda attention. However, when no contact was made with family members over a prolonged period, fears for his safety intensified.
By the time of his disappearance, he had graduated into more organised drug dealing, having spent the early part of his criminal past engaged in armed robberies.
He had associates in both Dublin and Galway and had regularly travelled to the west of Ireland as part of his drug-dealing activities.