One of the Australians among the people missing after a volcano eruption in New Zealand has been found alive.
Adelaide woman Lisa Dallow was found in a New Zealand hospital, relatives confirmed on Tuesday afternoon.
Three Australians are among the five people confirmed dead in the volcanic eruption on White Island, with the toll certain to rise.
It is understood Ms Dallow is being treated for severe burns in Hamilton Hospital, with her partner Gavin Dallow and 15-year-old daughter Zoe Hosking still unaccounted for.
Eight people were missing presumed dead including Ms Dallow, with 13 Australians, some with critical injuries, being treated in hospital.
Those fit to travel are likely to be transported to Australian hospitals as all New Zealand's burns units are at capacity.
Of the 47 people on or near the island, also known as Whakaari, when it erupted on Monday afternoon, 24 were Australians aged between 17 and 72.
Most were passengers from cruise ship Ovations of the Sea which was moored off New Zealand's North Island around 50km away.
A Sydney family of four, Ms Dallow's Adelaide family of three and a Brisbane mum and daughter are included on the Red Cross list of those missing since the eruption.
"This is a very, very hard day for a lot of Australian families whose loved ones have been caught up in this terrible, terrible tragedy," Prime Minister Scott Morrison told reporters in Sydney on Tuesday.
"I fear there is worse news to come over the course of perhaps today or over the next few days.
"This is a terrible tragedy, a time of great innocence and joy interrupted by the horror of that eruption."
New Zealand authorities have determined nobody on the island could still be alive.
The full extent of the injuries suffered by the 13 injured Australians is unknown.
"At this stage it is still too early to tell - we know there are a number in critical conditions," the prime minister said.
"Obviously there are quite severe burns issues and that's why they are in so many different hospitals because they have been taken to the various burns units across New Zealand."
An Australian Federal Police forensic team is on its way to New Zealand to help identify victims.
Australia is also sending extra consular staff to support those affected.
New Zealand Prime Minister Jacinda Ardern addressed parliament saying "our family in Australia has been heavily impacted".
"We feel the pull of our bond acutely at this time."
The Royal Caribbean cruise company was working to help guests and authorities in any way it could, a spokeswoman said.
The company had staff on site, was communicating with guests and families, while offering medical care, counselling and accommodation, she said.
"The news from White Island is devastating. The details that are emerging are heartbreaking," the spokeswoman said.
Mr Morrison praised medical teams caring for the injured Australians.
"Some of those Australians will be a long way away from loved ones and they will be there on their own, and unaware of what has taken place because of the nature of their injuries," he said.
Australians who have concerns about the welfare of their friends and family are being urged to try to contact them directly.
Failing that, people have been told to call the Royal Caribbean cruise company or Australia's consular emergency centre.
Australian Associated Press