She was being detained at Tullamore Garda Station.
A woman arrested in the Midlands as part of the investigation into the murder of Patrick Heeran has been released without charge.
She was being detained in Tullamore Garda station for questioning along with a man in his mid twenties who remains in custody.
Patrick Heeran disappeared from Mohill,Co.Leitrim in October 2011 - his body was never found.
Gardai say their investigation is still ongoing and a file on the arrests is being prepared for the DPP.
The 48 year old was last seen in Mohill in Leitrim eight years ago.
In 2018, his family made an emotional appeal for information on the TV show "Crime Call", which at the time Gardaí said received a very good response.
Yesterday afternoon, a man in his mid 20s and a woman also in her mid 20s were both arrested in the midlands area and are detained at Tullamore Garda Station.
The man can be held for up to 24 hours.
Asthma Society of Ireland Hold Workshop In Laois This Weekend
Laois TD Calls For Shorter Ambulance Deployment Distance
Uisce Eireann Publish Shannon Pipeline Consultation Submissions Report
70% Of Farming Families Lack Succession Plan
Mental Health Charity Triple Counselling Sessions After Citywest Protests
Westmeath Library To Close For Three Months From Today
Drug Usage On The Rise In The Midlands
Over 80 Jobs At Risk In Westmeath Tech Plant
Shannon Callows Farmers Demand Inclusion In Flood Management Group
Offaly Teachers Win National STEM Award
Appeal Lodged Against 600 Acre Laois Solar Farm Project
Government Funding To Benefit Midlands Historical Structures
Former GAA Referee Pleads Guilty To Indecent Assault
Laois TD Warns EU Plans Threaten Irish Neutrality
Almost One Million Cigarettes Seized In Offaly
Management Can Easily End Industrial Action - SIPTU
Westmeath Credit Union Manager Wins Lifetime Achievement Award
Midlands Readers Encouraged To Take Part in MS Readathon
Westmeath Town Strong Performer For Fibre Broadband
Ireland's Oldest Living Person With EB Publishes Autobiography