A 45-year-old father of three was killed when struck by an ambulance while walking home on the main Ring of Kerry road near Killorglin early yesterday.
Two separate investigations into the incident are being carried out by the Garda and the Health Service Executive (HSE).
The HSE yesterday extended its sympathy to the man's family.
The ambulance was on its way from Caherciveen to pick up a patient in Killorglin when the incident near the brow of a hill occurred at about 2.15am.
The man was named locally as John Carey, a married man with three children, the youngest of whom is a 14-year-old boy.
He was a short distance from his home on a road off the main N70 road at Tullig, 5km from Killorglin, when the incident occurred.
It is understood he had been in Killorglin and had taken a lift part of the way home.
Supt Michael O'Donovan, who is based in Caherciveen, said a detailed examination was being carried out at the scene.
The ambulance remained at the scene, and the N70 near Killorglin remained closed for much of yesterday.
It is understood the driver of the ambulance was treated for shock.
The man's body was removed to Kerry General Hospital, where a postmortem is to be carried out.
The number of fatalities on Kerry roads in 2006 is now 21, the county's highest ever, and over twice that in many other Garda divisions.
Kerry County Council has decided to appoint a road safety officer this year to promote safety awareness.
Also yesterday, four people were injured following a collision on the M4 near Enfield, Co Meath. Two vehicles were involved in the collision, which took place at about noon. The four people injured were brought to Mullingar hospital. One of them is said to be seriously injured, though the injuries are not thought to be life threatening.
The M4 was closed 2km from the toll plaza for some hours and traffic was diverted on to the N4 at Enfield. Anyone who witnessed the incident is asked to contact gardaí in Trim.
Meanwhile, a fifth person has been killed on the North's roads since Friday.
The latest victim was Seamus Graffin (58), from Oriel Road, Antrim, who died following an incident in Randalstown, Co Antrim, on St Stephen's Day.
His death brings to 125 the total number killed on the North's roads so far this year.
As a result, a senior PSNI officer, Insp Rosemary Leech, repeated a call for drivers to slow down and to take account of the short daylight hours and the road conditions at this time of year.
Earlier yesterday, the funerals took place of James McGuigan (30) and his eight-year-old daughter Lorna who died when their car left the road and hit a tree near Crumlin, Co Antrim.
Mr McGuigan's other two daughters remain in hospital following Friday's crash.
Two men were also seriously injured in a crash two miles from Clough, Co Down.
Police said five people were travelling in the car which left the road at a junction on the main road from the village to Castlewellan at about 4.30am yesterday.