Two brothers who lived at the West Auckland home outside where Connor Morris was killed have gone into hiding amid fears of retaliation.
After receiving advice from police, the young men have not returned to their home since Morris was killed two weeks ago.
Detective Inspector Greg Cramer, heading Operation Venice, would not say whether police had identified any suspects in the investigation.
The brothers weren't under police protection, but police had advised "a number of people". It is understood the brothers have been assisting police with their inquiries.
Morris suffered a fatal head injury during a confrontation outside a party in the West Auckland suburb of Massey. He was held by his partner of six years, Millie Elder-Holmes, as he lay dying.
Fears of reprisals by the Headhunters gang that Morris belonged to remain high. Fresh threats have been made on social media.
A family friend of the boys, who spoke on condition of anonymity, claimed they were "being looked after by police".
"All I know is that they're fine. They weren't involved in [Morris' death], but [are keeping their heads down] because of the involvement with those that are."
The brothers lived in a sleepout behind the home, .
It is understood they have been formally interviewed by police. One of the two had just become a father.
Police kept guard over the house for a week after the August 2 killing of Morris, a patched member of the Headhunters motorcycle gang.
But this week, the property was deserted. Glass covered the driveway and an overturned table had apparently been used as a barricade. The back door window was smashed.
The McDonald's wrappers and rubbish strewn across the backyard contrasted with the flowers laid on the grass verge in front of the house as a tribute to Morris.