The man being questioned about the murder of Waterford woman Meg Walsh (35) was freed without charge by gardaí last night.
The man, who is aged 40, was arrested at around 9.30am yesterday morning and was questioned at Waterford Garda Station.
He was freed after 9pm after having his initial six-hour period of detention extended for a further six hours.
Gardaí are understood to be preparing a file for the Director of Public Prosecutions.
Ms Walsh was reported missing to gardaí on October 2nd when she failed to appear for work.
Her body was found after a two-week search last Sunday floating in the River Suir opposite Thomas Meagher Quay in the centre of Waterford city. She is believed to have died as a result of severe injuries to her upper body.
The funeral for Ms Walsh took place on Thursday in the north Cork village of Killavullen.