Police have named a man they want to speak to in connection with the violent death of Radio New Zealand journalist Phillip Cottrell.
They say he is Nicho Allan Waipuka, aged 19, and should not be approached.
Mr Cottrell, 43, was attacked in Boulcott Street in central Wellington on his way home from work on The Terrace just after 5.30am on Saturday.
He never regained consciousness from the time of the attack and died in Wellington Hospital on Sunday surrounded by family and friends after being taken off life support.
Mr Cottrell had worked for Radio New Zealand as a bulletin editor for five-and-a-half years and had a condition which made his bones fragile.
Detective Senior Sergeant Scott Miller, says police believe Nicho Waipuka may have been in the vicinity of Boulcott Street at the time of the attack.
A post-mortem was completed on Tuesday. Police say Mr Cottrell had multiple fractures to his head, neck and left arm, including extensive brain injuries.
Mr Miller says the preliminary results indicate that his injuries were consistent with blunt impact trauma.
Police have identified a courier driver who was in the area at the time of the attack. They are still trying to find a man and a woman who were walking along Boulcott Street, as well as a taxi driver, and are looking at CCTV footage taken of the area.
Mr Miller does not think any of these people were involved in the attack, but says they could hold vital information in piecing together the events that led to Mr Cottrell's death.
Mr Miller says anyone with information as to Nicho Waipuka's whereabouts should contact Wellington police or phone the Crimestoppers line: 0800 555 111.