Gardaí are investigating if dissident republicans were involved in the murder of a 53-year-old man at his home in Clondalkin, Co Dublin.
Liam Kenny, a father of four, was shot several times in the upper body after a number of armed men tried to force their way into his house.
The shooting happened at around 4am at a house on Shancastle Avenue.
Mr Kenny was a member of Republican Sinn Féin, but the group said he left last July and became involved with a splinter group based in Limerick.
Detectives are trying to establish if he is the victim of a feud between the Continuity IRA and the Real IRA over control of an extortion racket in Dublin.
Gardaí have recovered what they believe is a getaway car used by the gunmen, a 10 D registered Nissan Qashqai, which had been stolen.
That car was found burnt out in the Steeples Estate in Chapelizod, around 3km from the murder scene.
A number of armed men tried to gain entrance to Mr Kenny's terraced house and then fired shots through a door panel.
Mr Kenny was in the hallway and was hit several times.
A number of family members were in the house at the time of the incident, none of whom were injured.
Mr Kenny was taken to Connolly Hospital Blanchardstown where he was pronounced dead.
