A 25-year-old man from Mangere has been charged with the murder of Epalahame Tuuheava and the attempted murder of his wife.
He is charged jointly with the two men arrested earlier Friday.
"Even after this third arrest for the murder and attempted murder, our investigation team will continue to identify and prosecute anyone else who played a part in this," Detective Inspector Tofilau Faa Vaaelua said.
Meanwhile, the two men arrested in relation to the investigation appeared in court Friday afternoon.
The pair were arrested and charged with murder and attempted murder after the death of Tu'uheava, 28, and serious injury of his wife, Tu'uheava, 25.
Both men charged were granted name suppression and any other details that may identify them are also suppressed - including any gang affiliations.
They appeared in the Manukau District Court; one wearing a boiler suit.
The men are due to make their next appearance at the Auckland High Court on May 30.
The judge said suppression of names and other identifying details will lift then.
The arrests follow the discovery of a man and woman on the side of Greenwood Rd, in Māngere, early last week.
The young parents had suffered gunshot wounds.
The surviving victim remains in hospital, recovering from her injuries.