A teenager has been arrested.
Adrian Harmon reports for RedFM News:
"This single vehicle collision happened at around 1am on the R518, Askeaton to Rathkeale Road.
One of the cars passengers, a man in his 20s ,was pronounced dead at the scene.
His body has been removed to University Hospital Limerick for a post mortem.
Another man, also in his 20s, has been taken to University Hospital Limerick, and is being treated for non-life threatening injuries.
The driver of the car, an 18-year-old man, has been arrested.
He's being questioned at Henry Street Garda Station under Section 4 of the Criminal Justice Act.
The road's currently closed and Forensic Collision Investigators are carrying out a technical examination of the scene.
Local diversions are in place.
Gardaí are appealing for any witnesses or anyone who was travelling on the route around 1am who may have camera footage to come forward."