Two brothers, aged 17 and 15, were among the four young people who died in a car crash in Co Kerry this morning.
A teenage girl was also pronounced dead at the scene; another young man died later in hospital.
A fifth person remains critically ill in hospital.
The collision happened at 7.10am on the Killarney to Mallow road on the N72 at Carrigeen.
Speaking on RTÉ Radio's News At One, Independent Councillor and Mayor of Killarney, Donal Grady, said the people of Killarney were shocked by the news.
He said the two brothers who died were from the town, another of the fatalities was from Castleisland, while the fourth was from Farranfore.
He said he understood the car went out of control at a bend in the road and hit a tree.
The scene is sealed off for a forensic examination and is expected to remain closed for some hours.
Diversions are in place and motorists are advised to avoid the area.