John Wirihana Isaac's body was found in the Waikato River on 18 January 2024. Photo: Supplied / NZ Police
A Hamilton man whose body was found in the Waikato River had been violently attacked, police say.
John Wirihana Isaac, 53, was found dead in the river by members of the public who had taken their boat to the river at about 6.30pm on 18 January.
Detective Inspector Darrell Harpur on Thursday said police believed it was only a matter of hours between when Isaac was killed and when his body was found in the river.
Harpur said while he could not go into details of Isaac's death, he had multiple injuries and it was a violent death.
"This all occurred in broad daylight, and we believe there are people out there who have information that will greatly assist our investigations," Harpur said.
Detective Inspector Darrell Harpur speaks to reporters at the Waikato River about the homicide probe into the death of John Wirihana Isaac. Photo: RNZ / Libby Kirkby-McLeod
Police wanted to talk with anyone who may have interacted with Isaac in the days leading up to his death, Harpur said.
Isaac was last seen at about 3pm on Wednesday 17 January, wearing black cargo pants and a green t-shirt with a print of a gas mask while shopping on Avalon Drive in the Hamilton suburb of Nawton.
Harpur said Isaac was quite distinctive, at 1.93 metres tall, and he often often rode a black bike around Hamilton.
Isaac had previous familial connections to the underworld and was known to police but was not a gang member, Harpur said.
He had three children and a grandchild, he said.
Harpur said police did not believe there was any ongoing threat to the public, but there would continue to be an increased police presence in the area in the coming days.