A man in his 70s was held overnight at Kilkenny Garda Station.
He was arrested yesterday in relation to the murder of Marie Tierney in 1984.
The man was being detained and questioned under section 4 of the Criminal Justice Act.
He was released this morning without charge and a file will be prepared for the DPP.
Marie was reported missing on the 22nd October 1984 having left her home in her car, which was located later on the 22nd October at Newpark, Kilkenny.
A comprehensive search was carried out by investigating Gardaí and Marie’s body was discovered on the Bleach Road, on 21st December 1984.
A murder investigation was launched.