A driver was killed when his car veered off the road into a tree.
The collision happened at Granardkill, Granard, Co Longford, sometime between 3am and 6am on Sunday morning.
The 39-year-old man at the steering wheel was pronounced dead at the scene and his body was removed to Mullingar General Hospital.
"There were no other persons in the vehicle at the time of the collision," said a Garda spokesman.
The road was closed for a time while forensic collision investigators carried out an examination.
Gardai have asked for any witnesses to get in contact.
Separately, gardai are investigating the death of another man in a single vehicle crash at Coolroe, Ballycullane, Co Wexford.
The 69-year-old died when the car he was driving veered off the road and into a ditch. No one else was involved.
His body was taken to Waterford Regional Hospital.
Investigators believe the collision happened sometime between 5.30pm yesterday and 9.30am on Sunday morning. They have also appealed for witnesses to come forward.