Police received a report, around 5:30pm on Friday, of a man being swept downstream after falling off his boat.
Eastern Bay of Plenty Area Commander Inspector Nicky Cooney says emergency services carried out an initial search of the area and located the vessel nearby.
She said a rescue helicopter, private helicopters and local jet boat operators also engaged in the search.
"Sadly, at this stage, the man remains outstanding."
On Saturday police furthered their search of the river, near the junction with Waiata Stream.
Cooney said police are using land-based and water-based resources, as well as a Police drone to carry out aerial searches.
"We continue to support the man's family at this difficult time."
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