A man in his 30s arrested in connection with the murders of Antoinette Corbally and Clinton Shannon was tonight released without charge.
Gardaí will prepare a file for the information of the Director of Public Prosecutions.
A man in his 30s has been arrested by Gardaí investigating a double murder in Ballymun last month.
Antoinette Corbally was shot on Wednesday, August 16, several times at the front of her home on Balbutcher Drive as the intended target, her convicted gunman brother Derek Devoy, fled the scene.
The second victim was Clinton Shannon, a locksmith from Swords, Dublin, who was hit by a number of bullets as he sat in a car on the street outside the property.
The man was arrested on Monday and is being held under Section 50 of the Criminal Justice Act, 2007 at Ballymun Garda Station.
He can be detained for up to seven days.
Investigating Gardaí are continuing to appeal for information.