Palmerston North area prevention manager Inspector Phil Ward said officers appealed to the man to come back to land, however, he disappeared under the water’s surface.
Due to the rough terrain of the river and limited visibility, emergency services were stood down about 1.30am, with a full rescue attempt underway at first light.
The operation has now moved to a “limited search phase”.
Ward said the decision was made after extensive searches of the river, Foxton estuary and surrounding areas.
“Police will continue to conduct drone sweeps of areas of interest, and patrols along Foxton Beach,” he said.
“Police thank Land Search and Rescue, Police Search and Rescue, Palmerston North Swiftwater Rescue, regional response teams, Coastguard Manawatū, and everyone else involved in the search operation.”
Police continue to provide support to the man’s family.