The woman in her 60s arrested earlier today in connection with the suspected murder of Brian McGrath in Co Westmeath in 1987 has been released without charge this evening.
A file will be sent to the Director of Public Prosecutions.
The woman had been arrested in connection with the discovery of human remains in Co Westmeath over 15 years ago.
Gardaí believe the remains are those of 43-year-old Brian McGrath, who disappeared in 1987, six years before the body was discovered.
Gardaí acting on confidential information searched land in the Coole area and found the remains buried in a field in November 1993.
They suspect efforts had been made to set the body alight before it was secretly buried.
When the body was initially found it could not be identified. A number of people were questioned by gardaí but no prosecution was taken.
Last May, following a review of the case by detectives from the Garda Cold Case Unit, the body was exhumed and fresh forensic tests led detectives to strongly believe the body is that of Mr McGrath.
