Police have arrested a 36-year-old man in connection with the murder of Robbie Lawlor in north Belfast.
Mr Lawlor, 36, was shot outside a house in Etna Drive in Ardoyne on Saturday.
He had been a suspect in the abduction and murder of Drogheda teenager Keane Mulready-Woods in January.
It is believed Mr Lawlor was a leading figure in a feuding criminal gang.
The suspect was detained on Tuesday night on suspicion of murder.
The PSNI believes a single gunman was involved in the Ardoyne attack.
Three other men and a teenager who were arrested have since been released.