Two men in their 20s were killed in road collisions at the weekend and a motorcyclist died as a result of his injuries in a crash last Thursday.
Gardaí at Thomastown, Co Kilkenny, are investigating a fatal traffic collision which occurred shortly before 2am on Saturday on the N9 at Kilfane, Thomastown.
A 20-year-old male pedestrian was fatally injured when he was struck by a car. The deceased man was removed to St Luke's Hospital, Kilkenny.
He was later named as Patrick Hayes, from Market Street, Thomastown.
In Co Kerry, a fatal traffic collision occurred at approximately 9pm on Saturday.
The 22-year-old driver of a car died in a head-on collision near a bend between the towns of Killorglin and Milltown.
He was named as Andrew Tattershall, of Iveragh Park, Killorglin, who was pronounced dead at the scene of the crash.
A front-seat passenger in Mr Tattershall's car, also a man in his early 20s, and two people in the other car were taken to Kerry General Hospital, Tralee. Their injuries are believed to be minor.
Meanwhile, the man who died in Friday's fatal road traffic collision between a jeep and trailer and a car on the new straight stretch of the N21 between Feale's Bridge and Hedley's Bridge in Co Kerry has been named as Ray Stryker (18), from Kilmaniheen West, Brosna.
The dead man was a passenger in the car and the driver was seriously injured.
Eighteen people have now died on Kerry's roads this year, a record high.
Garda Supt Michael O'Donovan, of Caherciveen, said it was the county's "worst ever year" on the roads.
He said that gardaí were greatly concerned, adding that some 12 people had died last year in collisions on the roads of Kerry.
"We are appealing to drivers to be aware of their behaviour on the road and to realise that everyone is responsible for their own behaviour when they sit behind the wheel," Supt O'Donovan said.
In Co Tipperary, a 19-year-old man has died following a road traffic collision in Clonmel. The collision occurred at 9.15pm last Thursday at Jackson's Cross, Cahir Road, Clonmel.
The deceased man was riding a motorcycle when he was in collision with a car. He was named as James Cassin, from Wilderness Grove, Clonmel.
After the collision, Mr Cassin was removed by ambulance to Cashel Hospital.
He was later transferred to Cork University Hospital, where he died from his injuries late on Saturday evening.