Searchers have found an upturned boat, but no sign of the fisherman last seen clinging to it at midnight.
The 24-year-old Rotorua man was fishing with two others off Bowentown Harbour last night when their boat overturned.
Police were alerted around 11pm when a 28-year-old man and a 10-year-old child were found washed ashore, alive but hypothermic.
SAR search boss Vince Ranger said they have today found the five-metre dinghy the group were in when it overturned.
"Much of the debris from the boat had been washed out including fuel cans, seats, but as of now, there has been no sign of the missing person."
The HMNZS Taupo is one of a number of vessels searching for the missing man.
Maritime Component Commander Jim Gilmour said the Defence Force is doing all it can to assist.
"As worrying as it will be for this young man's family, we are really hoping that a positive outcome will come from this search."
The ship joined the search at first light, and has been joined by three Coastguard vessels, a Coastguard plane are Surf Life Saving boats are also helping scour the ocean.
"I know everybody on board HNZMS Taupo will be doing their utmost to contribute to this search effort," Gilmour said.
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