A man (25) is due in court in Dublin tomorrow charged in connection with the murder of a man in Belfast earlier this year.
The man is one of nine people arrested in the past two days in Dublin, Dundalk and Belfast by police investigating the murders of Joseph Jones (38) and Edwards Burns (36), who died within hours of each other last March.
Three men and a woman were arrested in Dundalk, Co Louth, and Dublin.
A Garda spokesman said one of the three men is due in Dublin District Court tomorrow on charges connected with the death of Mr Burns and other charges related to the incident. The woman has since been released without charge.
Four men and a woman who were detained in Belfast are still being held at the Serious Crime Suite at Antrim Police Station.
The body of Mr Burns from the republican Ardoyne area was found in west Belfast, while the badly beaten corpse of Mr Jones from Poleglass was found in an alleyway off Elmfield Street in the north of the city.
It is understood the pair had been drinking together before being lured into a car. A third person was injured in the same attack.
Last week, the Independent Monitoring Commission said the two men were murdered by the Continuity IRA. It said Mr Burns and Mr Jones were "both former Belfast members (of the Continuity IRA) who had established a rival group in the same area".
Gardaí said the arrests in Dublin and Dundalk were made yesterday as part of an ongoing cross-border inquiry in co-operation with the Police Service of Northern Ireland.