A 65-year-old man found dead on mudflats in Northland had gone to check fishing nets and was later reported missing.
Police are investigating after the man's body was discovered next to the Wairoa River, also known as the Ruawai River, about 7am yesterday.
A police spokesman said the man had gone to check fishing nets and a member of the public reported someone had gone missing early yesterday.
His body was found further upstream from the river.
The death has been reported to the coroner and police would not release the man's name until his family had been advised.
An autopsy would be conducted to assist the coroner in determining the cause of death, police said.
Both police and Fire Emergency New Zealand attended a callout about 7am yesterday.
Police would not release details surrounding the circumstances of the man's death, where he was from, or if he drowned because that had to be determined by the coroner.
Water Safety New Zealand receives police reports after drowning incidents, but not yet on yesterday's case.
"While we cannot comment specifically on this incident as the details are yet to be confirmed, it is a tragedy and our condolences go to the family involved," spokesman Ben Christie.
He urged people to familiarise themselves with New Zealand's Boating Safety Code before they go out boating on seas, lakes and rivers this summer.
Christie said six people have drowned in Northland so far this year.
People should take lifejackets and wear them to increase their survival in the water because boats, especially those under 6m long, could sink very quickly, he said.
"The skipper is responsible for the safety of everyone on board and for the safe operation of the boat. Stay within the limits of your vessel and your experience.
"Take two separate waterproof ways of communicating so we can help you if you get into difficulties. Check the local weather forecast before you go as New Zealand's weather can he highly unpredictable."
Christie said safe boating and alcohol did not mix and things could change quickly on the water. Therefore, he said, people needed to stay alert and aware.