A man has been arrested after a loyalist supporter was shot dead in a supermarket car park in Bangor in County Down on Sunday.
35-year-old Colin Horner, who was with his three-year-old son at the time, was attacked by a lone gunman.
It is understood Mr Horner, from Carrickfergus, Co Antrim, recently relocated to Bangor amid fears he would be targeted in the same loyalist paramilitary feud that claimed the life of his friend George Gilmore two months ago.
Loyalist Mr Gilmore, 44, was shot dead in Carrickfergus in March.
Police Service of Northern Ireland (PSNI) Detective Superintendent Richard Campbell confirmed a link between Mr Horner’s murder and the long-running Carrick feud between rival loyalists was one line of inquiry.
The detective said the victim had just strapped his son into the back seat of his black Nissan Pulsar car, reg XFZ 4706, at 2.45pm when a lone gunman approached and fired at least three shots from a handgun.
"His three-year-old son was in the car and was immediately beside his father when he was shot dead in front of him," he said.
"So it’s a hugely barbaric act and something that will undoubtedly live with this young boy for the rest of his life."