Gardaí are now treating as murder the death of Olivia Dunlea whose body was discovered following a fire at her home in Co Cork in the early hours of yesterday.
A man in his 30s has been arrested for questioning.
He has had his period of detention extended this evening and, depending on rest periods, it is likely to be the morning before a decision is made on whether to charge or release him.
Gardai also have the preliminary findings of Dr Marie Cassidy's post mortem examination, which indicate that Ms Dunlea, 36, was violently assaulted before the fire started.
The fire at Ms Dunlea's two-storey, semi-detached home was first noticed by her neighbours at around 1.10am yesterday.
Gardai are appealing to anyone who was in the vicinity of Pembroke Crescent, Passage West Village, or adjoining roads between midnight and 2am.
Ms Dunlea had spent Saturday night socialising with friends at a local bar before returning home at around midnight.
Her three children, two boys and a girl aged between nine and 12, had spent the night with family and friends elsewhere, and neighbours initially thought that the house was unoccupied.
The blaze was well advanced when firefighters from Carrigaline and Cork city arrived.
Ms Dunlea's body was only discovered after they had brought the fire under control.