A man has been arrested in connection with the death of a woman on a ferry which docked at Rosslare Europort.
Gardaí say a "serious incident" broke out on the ship amongst a small group of people in a small area.
The woman was pronounced dead at the scene following a confrontation but gardaí say they are trying to establish the full circumstances surrounding the incident.
They believe a small number of people who knew each other were involved.
Watch: Colman O'Sullivan reports live from Wexford
The ship's captain made an emergency call around half an hour before the ship docked and the emergency services and a large force of gardaí were waiting for it when it arrived at 5.30pm from Fishguard.
The Stena Nordic has been detained in port, the return journey cancelled and waiting passengers were accommodated on the Irish Ferries sailing to Pembroke.
Gardaí are treating the death of the woman as suspicious and awaiting the results of the post-mortem examination to determine the cause of death.
The Office of the State Pathologist and local coroner have been notified.
The scene has been preserved for technical and forensic examination.
Gardaí have said there are no public safety issues at this time.
The man was arrested on board and is being detained under section 4 of the Criminal Justice Act at a local garda station.
He can be questioned for up to 24 hours.
All passengers and crew on the ship, which had arrived from Fishguard in Wales, will be interviewed as part of the investigation.
Stena Line cancelled its 7.30pm Rosslare to Fishguard sailing following the incident.
All passengers booked on that crossing were accommodated by Irish Ferries on their 8.45pm sailing from Rosslare to Pembroke.
