'Devastating loss': Sydney schoolboy brothers confirmed dead in volcano tragedy

The confirmed deaths of two teenage brothers has taken the death toll of Australians following New Zealand’s White Island volcano eruption to nine.

Berend Hollander, 16, and his brother Matthew Hollander, 13, who both attended Sydney’s prestigious Knox Grammar School in Wahroonga, were on the island when the volcano erupted on Monday.

“It is with the greatest sadness that I can confirm that Matthew Hollander (Year 8) and Berend (known at ‘Ben’) Hollander (Year 10) have passed away in hospital as a result of injuries sustained in the White Island volcano eruption,” the school’s headmaster Scott James wrote in a letter to parents.

Berend Hollander (left) and his brother Matthew Hollander (right) have died in hospital after sustaining critical injuries on the island. Source: AAP

“Please take some time to reflect on the lives of Matthew and Ben and this devastating loss for our community.”

Mr James described Matthew as a “vibrant” and “popular” student who loved sport, while he said his brother Ben was “compassionate and enthusiastic”.

The boys’ parents, Martin and Barbara Hollander, remain unaccounted for.

Gavin Dallow, 53, was confirmed dead on Wednesday, while his family said his step-daughter, 15-year-old Zoe Hosking, was presumed dead on White Island.

Brisbane mother and daughter Julie and Jessica Richards were also named as victims by their family who remembered them as an adventurous pair who loved the outdoors.

And the loss of three friends from Coffs Harbour - Karla Matthews, Richard Elzer and Jason Griffiths - was confirmed by their travelling companions late Wednesday night.

Jason Griffiths (left), Karla Mathews (centre) and Richard Elzer (right) have been confirmed as three victims that died following the eruption. Source: AAP

"We are incredibly saddened to have lost three of our closest friends," their friends Alex, Daniel, Ellie, Leanne, Paul and Samantha said in a statement issued by the Department of Foreign Affairs and Trade.

Mr Griffiths died in hospital after suffering burns to 80 per cent of his body in Monday's eruption while Ms Mathews and her partner Mr Elzer are among eight bodies believed still on the island where authorities say there is no sign of life.

New Zealand police have also listed Victorian woman Krystal Browitt as missing on the island.

All had taken a tour of White Island while on a cruise on the liner Ovation of the Seas which was moored 50km away on New Zealand's North Island.

Grieving family questions why tour went ahead

Mr Dallow's father Brian questioned if his son knew of the risks of visiting the island, home to New Zealand's most active volcano.

"Gavin was always one for being fairly articulate on what he did," Brian Dallow said on Wednesday.

"So, I think if he had known there was a danger he wouldn't have gone on it.

"I'm pretty well sure they weren't fully informed of the danger."

Authorities are yet to recover the bodies left on the island. Source: AAP

New Zealand authorities will examine whether the White Island tour company were aware of any dangers or increased risks of an eruption.

Mr Dallow's 48-year-old wife and Zoe's mother, Lisa Dallow, remains in a critical condition in Hamilton with serious burns.

She is one of around a dozen Australians in New Zealand hospitals who the RAAF will try to transfer home for treatment on Thursday.

Many have critical injuries suffered in the intense heat and toxicity of the ash and volcanic gas from the eruption.

Friend John Mickel said the family of Ms Richards, 47, and Jessica, 20, were "united in grief".

"The family have asked me to describe Julie and Jess as being outdoor, adventurous people... if there was an adventure that offered itself, then they would go," he said.

Fears are also held for the Hollander and Langford families from Sydney.

Anthony and Kristine Langford have not been heard from and their daughter Winona, 17. Their son Jesse, 19, has reportedly been identified as one of those being treated in hospital.

With AAP

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