The man who had been arrested by gardaí investigating the killing of Ashling Murphy has been released.
The 23-year-old primary school teacher was attacked while out for a run along the canal in Tullamore, Co Offaly yesterday afternoon.
Vigils will take place across the country today in her memory.
A man was being questioned in relation to the attack; however, he has now been released from custody and is no longer considered a suspect in the case.
In a statement, gardaí said: "The male who was arrested and detained by An Garda Síochána investigating this fatal assault has now been released from this detention.
"This male has been eliminated from Garda enquiries and is no longer a suspect."
Gardaí are continuing to investigate the assault, and are appealing for information about a mountain bike.
Anyone with information is asked to contact Tullamore Garda Station on 057 932 7600, the Garda Confidential Line on 1800 666 111, or any Garda Station.