'It hurts us': Fears bodies of missing volcano tragedy victims washed out to sea

New Zealand police will scale down their search for bodies missing from last Monday's Whakaari eruption, saying they are "deeply sorry" for their failure to complete the task.

"That has been our mission throughout. Firstly to save people and then to recover people," deputy commissioner Mike Clement said on Wednesday.

"It hurts us. It hurts our people and it hurts everyone in the community when we don't achieve that.

"We are deeply sorry we haven't until this time, been able to return these bodies."

Of the 47 adventure tourists and guides on Whakaari during the blast, all but Sydney teenager Winona Langford and Whakatane tour guide Hayden Marshall-Inman have been accounted for.

Police had remained positive and committed to returning the bodies to families since establishing the retrieval operation.

They've made two trips to the surface of the active volcano, several dive explorations in nearby waters and many aerial searches, by plane, helicopter and drone.

Police are now firm in their belief that a major storm on the night of the eruption has washed the bodies to sea.

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But nine days after the eruption, with a vast expanse of the Bay of Plenty to search, police admit they are struggling.

"The reality is we've dived in the area where the body was last seen and we can't find it," Clement told Radio NZ.

Local police will now take over command but retain an Eagle helicopter and the Deodar vessel to enable the water search - which has expanded to North Island bays.

"What we do is model and put ourselves in a position where we think things could eventuate and if all of those things are playing out then we will find it," Clement continued.

"And if they don't, we won't."

The heartbreaking scenario comes after the jubilation of last Friday, when a crack defence force squad retrieved six bodies from nearby the crater.

Missing guide still on the island he loved

Family of Marshall-Inman were in Whakatane for the successful mission only to learn that he wasn't among the six bodies recovered.

Hayden's brother Mark Inman said the family was coping with its grief as best it could.

"We're staying positive. You've got to keep positive thoughts so that you can forever hope that he'll return home one day," he told 1News.

"The only positive that would come out of him not returning is his absolutely love of the island and his passion for White Island.

He'll forever be a guardian out there."

Marshall-Inman had a long fascination with the volcano, with Inman saying the fateful visit was his 1111th to the island.

"You could speak to him every day about it and he'd give you a new fact or something new that had happened on the island," he said.

"He loved sharing such a beautiful place with so many people, both Kiwis and internationals."

A reception will be held on Friday in Whaktane for Marshall-Inman's life.

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