A 41-year-old man is being questioned in connection with the discovery of a man's body in the Dublin Mountains.
The 64-year-old had gone out to walk his two dogs on Thursday and a search, involving the Dublin/Wicklow Mountain Rescue team and the Glen of Immal Mountain Rescue Team, was launched after he did not return.
After his body was found, it was discovered that Mr McCoy had sustained serious head injuries.
Gardaí then launched a murder investigation, resulting in the arrest of a man yesterday afternoon.
The arrested man is being questioned at Tallaght Garda Station.