He is known to the chief suspect.
A man well-known to the chief suspect of the Ashling Murphy murder investigation has been arrested on suspicion on withholding information.
The development comes as the chief suspect continues to be questioned at Tullamore Garda Station.
The second male is detained at a Garda Station in the Eastern Region.
He is being questioned in relation to potential withholding of information.
A decision to either charge or release the chief suspect in the murder of Ashling Murphy is expected to be made today.
The 31-year-old suspect was still being questioned about her murder by specialist detectives this after his arrest at St James’s Hospital in Dublin yesterday.
The suspect was then brought by Gardaí to Tullamore garda station where he was interviewed throughout the day and into the night.
He can be detained for up to 24 hours excluding periods required for rest between midnight and 8am, or any medical treatment that could take place outside the station.
Today marks a week to the day since the 23 year old went for a run along the canal bank in tullamore and was violently assaulted.
The 23 year old teacher from Offaly was laid to rest yesterday.
Kacey O' Riordan reports:

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