Two people due to give evidence in Conor McGregor's appeal against being found civilly liable for sexual assault were arrested for alleged perjury.
Samantha O'Reilly and Steven Cummins were arrested yesterday morning by the Garda National Bureau of Criminal Investigation.
Detectives had earlier this year launched an investigation after the couple sensationally withdrew their evidence in the appeal.
In August, the Court of Appeal confirmed it would also refer an allegation of perjury, relating to Mixed Martial Arts fighter Conor McGregor, to the Director of Public Prosecutions.
Judge Isobel Kennedy said she would pass material to the DPP concerning McGregor's dropped allegation that Nikita Hand was assaulted by her own partner.
Perjury offences, including inducing someone else to commit perjury, carry a maximum penalty of a €100,000 fine or up to ten years in prison.
Ms Hand, a 36-year-old mother of one, was awarded just under €250,000 in damages by a High Court jury last year, after claiming she had been violently raped by McGregor in a Dublin hotel.
Earlier this year, McGregor had said he would call fresh evidence from two of Ms Hand's former neighbours in Drimnagh, Dublin - Samantha O'Reilly and Steven Cummins - in support of his appeal. The pair had signed sworn statements saying they had seen her being physically attacked by her partner at the time, Stephen Redmond, on December 9, 2018, after she returned home from her encounter with McGregor.
A Garda spokesman confirmed that two people had been detained.
He said: 'Gardaí have arrested a male and a female (aged in their 30s) in connection with an ongoing Garda National Bureau of Criminal Investigation investigation today, Thursday September 11.
'They are currently detained under the provisions of Section 4 of the Criminal Justice Act 1984 at Garda stations in the Dublin area. Investigations are ongoing. No further information is available at this time.'
In a sworn statement, Ms O'Reilly alleged she had seen a 'heated row' from her upstairs window in Drimnagh on the night of Sunday, December 9, 2018 - a few hours after Ms Hand left the Beacon Hotel following her encounter with McGregor.
She alleged that Ms Hand was punched and kicked on the ground by Mr Redmond during this row.
McGregor's legal team suggested that this explained the very serious bruising that was seen on Ms Hand's body in the morning, when she was taken by ambulance to hospital.
McGregor had claimed he had consensual sex with Ms Hand, and that he had not caused the bruising.
However, as the appeal then opened, Mark Mullholland, a barrister for McGregor, said that 'we cannot sustain that ground of appeal'.
He said this was related to forensic evidence that had been sought from retired State Pathologist Professor Jack Crane.
He said Professor Crane had been approached 'to corroborate the account of Samantha O'Reilly'. In the absence of this corroboration, he said, and taking a 'holistic view' of the case, there was no sustainable ground of appeal.
