Mr Maheno's body was to have been removed from the house yesterday afternoon.
Neighbours said they had heard shouting, and thought it was some sort of domestic incident, but then heard two shots.
"We heard some shouting and then didn't think anything of it. We heard a police siren and thought okay, that's domestic violence, it's all sorted," Alistair Glanvill said.
He had not known his neighbours, but there had been no problems.
Detective Senior Sergeant Burke said police were still investigating what issues might have led to what he described as a tragedy that had left many people devastated. A firearm had been seized and police were not looking for any other offenders or weapons, but would be pleased to hear from anyone who could offer any information. (Phone the Kaitaia police station on 09 408-6500).
Police had been unable to talk to Mrs Maheno, but her two children were physically unharmed. It was believed that they were not at the address at the time, and were now in the care of extended family.
Twenty-two police staff from around Northland were working on the investigation. A scene examination was carried out yesterday, with forensic examinations and post-mortems to be conducted to determine the causes of death.
Detective Senior Sergeant Burke also reassured the community.
"Clearly when something as tragic as this occurs there is a lot of apprehension. However, the person we believe to be responsible has handed himself in and we have located what we believe to be the weapon," he said.