Bay of Plenty District Commander Superintendent Tim Anderson said authorities are moving from a "rescue operation into a recovery phase".

"This is heartbreaking news for us and obviously the families involved," he said during a press conference on Saturday afternoon.

Six people are still unaccounted for and police expect their names to be released this afternoon.

Anderson confirmed they have found human remains in the search.

He said the deceased were found in an area search teams expected them to be, but he wouldn't specify where.

Anderson said the identification process could take days.

"There's still a lot of mud and other aspects [around the site] so my primary consideration today is actually the safety of the staff working on it."

Asked about the numbers unaccounted for, Anderson confirmed there were six people authorities had been searching for.

Anderson said there were "really strict parameters around those that are working on site right now" due to the unstable ground.

"It rained last night, it's just rained before."

'Harrowing job' for emergency teams

Fire and Emergency Assistant National Commissioner David Guard said it had been a "harrowing job" for first responders during the emergency.

"My respect goes out to the families, but equally for emergency workers, and particularly those working on site. It's tough for them as well."

Police are now the lead agency as the operation moves into the recovery phase.

Person in custody after breaching Mount cordon

A person who broke the cordon around the Mount Maunganui operation this morning is in custody.

Tauranga Mayor Mahé Drysdale said they will "take every opportunity to punish those people because it's unacceptable behaviour".

Questioned whether Mauao could face a permanent closure, Drysdale said council would be having those discussions "at a later date" with local iwi.

"Our thoughts and our priority is returning the remains of the people that remain here."

Deceased will be transported to Hamilton - Chief Coroner

The Chief Coroner shared her condolences for those families and friends who have lost loved ones.

She said human remains have been found and are now in the custody of the coroner.

The deceased victims will be transferred to the mortuary in Hamilton and will be kept there until they can be reunited with families.

While acknowledging that family members are desperate to be reunited with their loved ones, the Chief Coroner said.

 She said identification can be a "painstaking, complex, lengthy process" that takes time".

"The last thing we want is to have any familiar traumatised by having a person other than their family member returned to them."