Murder detectives have until tomorrow to charge or release a father-of-two being questioned in connection with the killing of a childcare worker.
The 41-year-old was arrested by officers investigating the death of Elaine O'Hara, whose body was found in the foothills of the Dublin Mountains last month.
He was detained during a dawn raid at a house in the exclusive Foxrock area of Dublin.
Gardai can question him until tomorrow afternoon at the latest. He is being held at Blackrock Garda Station under Section 4 of the Criminal Justice Act 1984.
Ms O'Hara, 37, disappeared in August last year after leaving her home in Belarmine Plaza, Stepaside, and later being seen at a footbr idge over a railway line at Shankill, Co Dublin.
Detectives believe she might have met her killer on an adult contacts website.
Ms O'Hara was described by her family as a popular woman, but was understood to have been vulnerable and had been treated in hospital for depression.
She was also described as a trusted childcare assistant and worked in a newsagent's in Blackrock.
It is understood she had been using contact websites in the months leading up to her disappearance, and forensic experts have pored over internet records to build a list of people she came into contact with.
Ms O'Hara's remains were uncovered by a dog in the Killakee area, near Rathfarnham, on September 13.
Handcuffs and restraints were found 20km (12 miles) away at Vartry reservoir near Roundwood, Co Wicklow, after some of Ms O'Hara's belongings were discovered at the same spot during a spell of low water.