Prime Minister Jacinda Ardern has told Parliament that there are questions which "must be asked" about the White Island eruption, and those questions "must be answered".
She revealed that police and Worksafe would be issuing statements setting out that process later today. Police have since announced a criminal investigation is being launched.
Ardern made the comments during her official statement to Parliament this afternoon.
She told MP there was "no limit" to New Zealand's capacity to embrace those impacted by this tragedy.
"The scale of this tragedy is devastating," she said this afternoon, of the eruption on White Island.
Ardern said there was much work to be done over the coming days and weeks.
"We know, too, there will be bigger questions in relation to this event. These questions must be asked and they must be answered," she said.
"But our focus now is on discharging our duty of care to support those affected and that is also the focus of the Police."
Ardern also revealed that those injured or missing included those from Australia, the US, UK, China, Germany, Malaysia as well as New Zealand.
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"We share in your grief and sorrow and are devastated," she said of the countries with people impacted by the tragedy.
"We will do everything to support you as you have supported us in times past."
Officials have confirmed that five people have died and there are eight people missing.
Speaking to media before going into the House the afternoon, Ardern said she had spoken to one of the helicopter pilots who was on the island in the immediate aftermath.
"He confirmed that, tragically, everyone who was alive and survived was taken off the island – that is absolutely tragic."
She confirmed that what happens next, will be a recovery mission.
"All of the information provided to the police from those operators who were on the ground pulling survivors off the ground was that there was no one left to rescue.
Back in the House, Ardern said no signs of life had been detected despite a number of air sweeps over the island.
"Those pilots made an incredibly brave decision under extremely dangerous circumstances.
"I'm sure all of this House would wish to pay tribute to them."
Foreign Affairs Minister Winston Peters confirmed that and said the Government was writing to the countries of those impacted by the eruption "as we speak".
He said Australia and the whole of the European Union have offered their support.
"But the nature of that, if it's something we will use, is a very good question because we think we have the resources that are required."
He would not say what that support was – "what they have said was, 'we can possibly help, give us a call'".
Finance Minister Grant Robertson said it was too soon to say what sort of financial assistance the Government would provide.