A 24-year-old man was rearrested by gardaí this evening in Portlaoise investigating the murder of 30-year-old Aoife Phelan.
He is being held at Portlaoise Garda Station under Section 4 of the Criminal Justice Act 1984.
A garda spokesman confirmed the man arrested is the same man who was released without charge from custody last night.
Meanwhile, a post mortem examination on the body of a woman discovered earlier today is underway at Tullamore General Hospital.
State Pathologist Dr Marie Cassidy is conducting a preliminary examination on the body which was located during a search for the a pregnant 30 year-old woman.
Gardaí investigating the murder of Aoife Phelan confirmed the discovery of a body at a press conference in Portlaoise this afternoon.
Superintendent David Taylor said: "Shortly after 11am this morning, Gardaí as part of a search discovered a body at a location known as Timahoe Road, Portlaoise, Co Laois."
"The scene was immediately sealed off for a full technical examination which is now underway and the office of the State pathologist has been notified and Dr Cassidy has arrived at the scene to carry out a preliminary examination."
Supt Taylor confirmed the body had been found at a location where searches had been taking place last Monday afternoon.
A large scale water and ground search around the River Barrow in Co Kildare has now been called off, he confirmed. "A number of searches have taken place over the last number of days as a result of this investigation, that was part of a number of planned searches," he explained.
According to Supt Taylor, "the Phelan family have been made fully aware of all the developments this morning and our family liaison officer is in constant contact with them."
He said gardaí were not making any further appeals.
"We have had exceptional help from the public and I would like to take this opportunity to thank the public for their immense help in this investigation. Without them we would not be able to progress the investigation."
Gardaí have sealed off a section of road on the Timahoe Road close to where the discovery was made.
Elsewhere, a large number of family, friends and neighbours have gathered at the Phelan household at Cashel, Ballyroan in Co Laois.