A 26-year-old woman was detained today in connection with the killing of Martin Morgan in Antrim last July.
She was being questioned about the death of the 41-year-old who was shot dead at his home at Firmount Drive in the Greystone estate.
Just five weeks earlier he had been released from jail where he had served a sentence for drugs-related offences.
Detectives hunting the killer or killers believe they fled the scene down an alleyway into the Ballycraigy estate.
A 35-year-old man arrested for questioning about the incident earlier this week was released without charge on Tuesday.