GardaI are preparing a file on a person recently arrested as part of their probe into the murder of dissident republican Alan Ryan.
During an update at Dublin Coroner's Court of the investigation into Ryan's death, Det Insp Tony Howard said the file is being prepared for the Director of Public Prosecutions following the arrest of the individual just over six weeks ago.
A woman in her early 30s was arrested on August 20 by detectives investigating the gangster's murder.
She is not suspected of having any active role in the murder, but is believed to have key information about the activities of the drugs gang that carried it out.
The woman is the girlfriend of a major figure in the gang.
Two people are already facing charges arising from the investigation, but these are not directly related to the murder.
Ryan (32), from Grange Abbey Drive, Donaghmede, Dublin 13, was gunned down on the street in broad daylight at Grange Lodge Avenue, Clongriffin, on September 3, 2012.
He was a leading member of the Real IRA in Dublin and gardai considered him a significant crime figure.
He was killed when a gunman approached him from behind as he walked on the street with two friends.
The killer opened fire and shot him multiple times.
Ryan's paramilitary-style funeral was interpreted as a show of force by the Real IRA and sparked huge controversy.
The father-of-one's murder is understood to be part of an ongoing gangland feud.
The inquest into his death was opened in October, 2012 but was adjourned at the request of gardai.
It has been adjourned several times since then to allow the investigation to continue.
As Det Insp Howard requested another adjournment, the Ryan family's solicitor, Michael Finucane, said that while they appreciate the inquiry is ongoing and the investigation complicated, the continual adjournment of the inquest is "not something that can be done indefinitely".
He told the coroner that the family would consent to a final adjournment, but that after that they will be requesting that preparations be made for an inquest hearing.
"We are more than two years from the murder of Alan Ryan and at some point an inquest is going to have to be held," he said.
The inquest was adjourned for further mention on February 9.