A man has been arrested following the death of a woman found seriously injured on a roadside.
The 35-year-old woman was discovered by the Couse Bridge roundabout on the outer ring road of Waterford city shortly after midnight.
The woman was found by gardaí and taken by ambulance to Waterford Regional Hospital where she died.
A 29-year-old man was later arrested. He is being questioned under Section 4 of the Criminal Justice Act.
Both the man and the woman are understood to be from Lithuania.
Gardaí said the scene where the woman was found has been preserved for a technical examination.
The road between Couse Bridge roundabout, Airport Rd roundabout and Ballindud Rd roundabout was closed.
Gardaí have appealed for witnesses who may have seen suspicious or unusual activity in and around the Couse Bridge roundabout or approach roads between 11.30pm and 12.10am.
Additional reporting: PA