Updated: 9pm
A man in his 50s, arrested on Tuesday for possession of a handgun, is now formally detained in connection with a fatal shooting which occurred on August 26th.
The man was arrested shortly after 10pm on Tuesday after gardaí responded to reports of an incident at a premises in Carlow town.
Officer recovered a firearm and the man was arrested at the scene. He was taken to Carlow Garda station where he is being held under Section 30 of the Offences against the State Act, 1939.
The updated offences for which the man is being detained relate to the fatal shooting of Conor O'Brien last week.
The 19-year-old was discovered with a fatal gunshot wound outside a house in Enfield, Co Meath on Friday morning.
The firearm seized on Tuesday has been sent for ballistic examination. Gardaí said no further comment would be made at this time.
