A person in their 70s died suddenly at the Esk River, Hawke's Bay, on Thursday afternoon.
Emergency services were called to the river in Eskdale about 2.23pm.
Police said the death was "potentially a medical event", rather than a drowning.
Fire and Emergency New Zealand said the medical event was attended by two fire trucks.
A FENZ spokeswoman said firefighters assisted St John Ambulance staff for two hours and 45 minutes.
