An 18-year-old was killed when the car he was driving collided with a truck and another car at Kilcogy
Investigations have been launched into crashes which have claimed the lives of three people over the last two days.
The incidents in Dublin, Carlow and Cavan have left communities in shock.
A teenager was fatally injured when the car he was driving collided with a truck and another car at Kilcogy in Co Cavan at approximately 7.30am this morning
Nobody else was injured in the crash.
Meanwhile, gardaí are appealing for witnesses after a 29-year-old man was fatally injured in crash near Carlow Town last night.
The male pedestrian was hit by a vehicle on the Carlow to Castledermot road at approximately 7.20pm last night.
He pronounced dead at scene, and his body was taken to Waterford Regional Hospital where a post mortem examination is to be arranged.
The male driver of the vehicle was uninjured.
Gardaí have closed the road to facilitate Forensic Collision Investigators and diversions are in place.
The man was the second person to die on Irish roads on Christmas Day.
Early yesterday a teenage boy died when his motorcycle crashed into another bike on Cherry Orchard Avenue in Dublin.
Separately, GSOC are investigating a separate collision yesterday between a garda patrol car and a motorbike in the Summerhill area of Dublin, which has left a man in serious condition in Beaumont Hospital.
Anyone with information on any of these incidents is asked to contact Gardaí.
The three fatal crashes bring to over 160 the number of people who have died on our roads so far this year.