A 23-year-old man arrested in connection with the murder of Daniel McKay has been released.
A spokeswoman for the PSNI said detectives from the serious crime branch had released the man unconditionally.
Mr McKay, a 36-year-old father of one was shot dead at his home in the Longlands area of Newtownabbey, Co Antrim last Thursday night.
He was hit a number of times at close range, at least once in the face. He died at the scene.
The detective leading the murder hunt said officers are investigating a possible drugs link and could not rule out the involvement of dissident republicans.
Mr McKay, who has a 10-year-old child, was known to police but was not considered a senior criminal.
Three other men aged 41, 50 and 28 arrested in connection with the shooting were also released.