A man (21) died early this morning after he was hit by a car in Arklow, Co Wicklow.
Following the incident on Arklow's main street at 2am, he was brought to Loughlinstown Hospital where he died.
The driver of the car was arrested and subsequently released pending analysis of a sample taken for suspected drink driving.
In Ashbourne, Co Meath, a teenager (17) died following a crash at 7.25pm. He was the front-seat passenger in a one of two cars that crashed on Castle Street.
He was taken to Our Lady of Lourdes Hospital, Drogheda, Co Louth, where he died overnight.
Gardaí at Buncrana, Co Donegal, meanwhile, are investigating a fatal road traffic collision at Quigleys Point, at 6.05pm yesterday.
A 62-year-old male cyclist was fatally injured when his bicycle was struck by a van on the Muff to Moville Road. The man died at the scene.
The road remained closed until this morning to allow for technical examination.