A post-mortem examination will be carried out today on the body of a 21-year-old man who was found seriously injured in a rural border area.
Paul Quinn, from Cullyhanna, was found at farm buildings near Castleblayney in the border county of Monaghan shortly after 6pm on Saturday, and died a short time later in hospital.
It is believed he was lured to the remote area and attacked.
His family yesterday blamed members of the Provisional IRA for the killing.
They claimed he had previously been involved in an altercation with them and was ordered to leave the country, but he refused.
Sinn Féin Northern Assembly Minister Conor Murphy MLA said he did not believe there was republican involvement in the killing.
Both the Police Service of Northern Ireland (PSNI) and An Garda Síochána would not comment on the claims but said they were investigating fully.
A garda spokeswoman said a post-mortem examination would be carried out at Our Lady of Lourdes Hospital in Drogheda, Co Louth, the results of which would determine the course of the investigation.