The elderly man arrested in connection with the murder of Marie Tierney in 1984 has been released without charge.
The arrest was made on Wednesday and the suspect was being held under section 4 of the Criminal Justice Act 1984.
In a statement this morning, a garda spokesman said: "The man in his 70s arrested in relation to investigation into the murder of Marie Tierney in 1984 has been released without charge.
"A file will be prepared for the Director of Public Prosecutions."
It is understood that a key witness came forward in recent weeks leading to a significant breakthrough in the investigation.
Kilkenny woman Marie Tierney was reported missing on October 22, 1984.
Her body was found on the Bleach Road in Kilkenny nearly two months later. The discovery sparked a murder investigation.
Her car was found at Newpark on the day she was reported missing by her husband Jim.
A comprehensive search of the county was carried out before her body was found.
In October 2018, Marie's body was exhumed from Conahy graveyard and, after a postmortem, the remains were reinterred in the cemetery.
