Edwin Maheno became incensed, loading his .22 rifle and shooting Ivan Maheno in the head, despite profuse apologies from the victim, followed by a shot to the right cheek.
Carmen Maheno ran to investigate and struggled with the accused, who punched her in the head, struck her in the abdomen with the rifle barrel and then in the head with the butt as she crouched on the floor. There was a second struggle as Maheno tried to reload the rifle.
When Carmen Maheno heard another round enter the chamber, she ran toward a neighbouring farm fence, the accused chasing her and shooting her in the back of the head, then in the buttocks. He then drove away from the house, still in possession of the rifle, telling an uncle he met at the bottom of the driveway that he had fatally shot the victims. He then drove to an aunt's house, telling her also, before returning to the home he and his victims had shared, smashing the television set and stamping on Ivan Maheno's body.
He collected some items from his room, then, still in possession of the rifle, drove to the Kaitaia police station. Unable to find anyone, he drove to his mother's house at Ahipara. Unable to find her, he returned to the police station and surrendered himself, stating he had fatally shot two people.
He told police he had been angered by the way the victims had treated him since they moved into the house, which Ivan Maheno had inherited and where he (Edwin Maheno) had grown up, that they had not respected the family homestead, and that he had killed them so the property would go to other siblings.