Tales of heroism, devastation and horrifying injuries emerged on Tuesday after New Zealand's smouldering White Island volcano exploded, killing an estimated 13 people.
Prime Minister Jacinda Ardern said five people had died and eight more were presumed dead after Monday's eruption, while the dozens injured had been airlifted to hospitals across the country.
Among the 47 people caught on the island during the sudden eruption were tourists from Australia, the United States, Britain, China, Germany and Malaysia, as well as local tour guides.
Amid questions over why tourists were allowed to visit the volcano, police announced a criminal investigation into the circumstances of the deaths and injuries.
'Scene of devastation'
Ardern praised the crews of four rescue helicopters for landing on the island soon after the eruption.
"Those pilots made an incredibly brave decision under extraordinarily dangerous circumstances in an attempt to get people out," she told reporters.
Intensive care paramedic Russell Clark was among those dispatched by helicopter to the caldera, which sits semi-submerged 50km's out to sea.
There he found an "overwhelming" and "shocking" scene of devastation.
"We didn't find any survivors," he told TVNZ, remembering a dust covered helicopter grounded with its rotor blades damaged.
"I can only imagine what it was like for the people there at the time - they had nowhere to go and an absolutely terrible experience for them."
New Zealander Geoff Hopkins' tour boat was leaving the island when a huge plume burst from the volcano - at what scientists said was supersonic speed - followed by a "menacing" and fast-moving cloud of grey ash.
Despite the danger, Hopkins said the boat moved closer to the shore after seeing survivors who had jumped from the island into the sea to escape.
Eruptions, poisonous gases and choking ash
"I don't think there was anyone that came off who wasn't badly burnt," he told the New Zealand Herald, describing how victims screamed and went into shock as fellow tourist tried to tend to their blistered skin.
Top New Zealand health official Pete Watson said 27 of the 34 survivors were being treated for burns to more than 71% of their bodies.
"It's important not to underestimate the gravity of the injuries suffered," he said.
After an initial rush, concerns about further eruptions, poisonous gases and choking ash stalled efforts to recover bodies.
The risks were underscored Tuesday when a large, but harmless 5.0 magnitude earthquake struck to the east of the disaster zone.
'Very hard day'
"To those who have lost or are missing family and friends, we share in your unfathomable grief and in your sorrow," Arden said, just months after managing another national crisis during Christchurch's deadly twin mosque attacks.
Many of the victims are believed to be Australian, with Prime Minister Scott Morrison warning his compatriots to brace for the worst.
He said there were fears that three of the five dead were Australian, and another eight citizens were unaccounted for.
"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," he told reporters in Sydney.
The Malaysian government said one if its citizens had died and two British women were confirmed to be among those injured.
The eruption at White Island - also known as Whakaari - occurred on Monday afternoon, thrusting a thick plume of white ash 3.6km's into the sky.
When the blast occurred, it was being visited by a group of more than 30 people from a Royal Caribbean cruise ship, the Ovation of the Seas, which left Sydney on a 12-day voyage last week.