Stiofan MacGabhann (29) was arrested in Sydney on Wednesday in connection with the murder of couple Thomas O'Hare (33) and Lisa McClatchey (21). Both died from their injuries after a gang of up to six men broke into their home on Foley Road, Keady, Co Armagh, on November 6, 2006. They were beaten with hammers and doused in petrol before being set on fire.
Mr MacGabhann was the latest suspect to be arrested in the case, following the extradition of brothers Niall (37) and Martin Smith (40) last month.
They were arrested in Co Dublin and Co Louth on December 12. During a High Court hearing, both consented to extradition to face charges in the North.
Mr MacGabhann, who is facing extradition from Australia, appeared at Sydney local court yesterday following a PSNI request for his arrest. He is due in court again on February 1.