Gardaí attended the scene of an assault in Kilkenny City on the Hebron Road at around 12:45 this afternoon.
They discovered a man in his 40s with serious injuries and he was brought to St Luke's General Hospital, however he died of his injuries.
A man in his late 20s was arrested at the scene and is being questioned at Kilkenny Garda Station.
The scene has been preserved and the office of the state pathologist has been notified.
Gardaí are appealing for witnesses and want to speak to anyone who was on the Hebron Road this afternoon between 12.30 and 1 pm , including any road users who may have dash cam footage.
Gardaí say they are investigating all the circumstances surrounding the fatal assault.
