Video shows the moment tour guide realises volcano could erupt any second

Video has emerged of tourists walking on a New Zealand volcanic island not long before it erupted killing dozens of people.

Allessandro Kauffmann was one of the people who visited White Island, off the east coast of the Bay of Plenty on New Zealand’s North Island, on Monday before it erupted about 2.10pm local time.

Mr Kauffmann shared video of his visit to the island, and its subsequent eruption, on his YouTube channel to show what it was “like before and after the eruption”.

He’s seen walking with dozens of tourists wearing hardhats. Captions in Portuguese point out the group visit a lake which is the “central part” of the volcano. 

Allessandro Kauffmann with a tour group on the day a volcano erupted on White Island. Source: YouTube/ Allessandro Kauffmann

Tour guide remarks about worrying change in lake colour

Steam billows out.

The tourist notes in his captions the lake changes colour - it’s “usually greener” but on Monday it was a “grayish, white colour”.

The group then walk near a number of coloured rocks with water bubbling from the heat.

“I’m a little bit worried about why it’s going green,” a man, believed to be the guide, says.

Ruins from old mining operations on the island are seen and the group investigate them.

A man is heard saying he's concerned about the water turning green. Source: YouTube/ Allessandro Kauffmann

They then leave the island before video cuts to an enormous plume from the eruption. Tourists film the smoke from the boat as they depart.

“Go inside, go inside,” one man yells as a woman films.

The captain reiterates this asking everyone to get “inside the boat now”.

“That’s terrifying,” a woman says.

Another asks, “Are we going to be OK?”

The boat then turns back to rescue survivors. A number are seen clamoured at the water’s edge.

The group turns their attention to the ruins. Source: YouTube/ Allessandro Kauffmann

Sixteen people dead

As of Thursday, 16 people have been confirmed dead from the eruption.

Two of those confirmed dead on Thursday were brothers Berend Hollander, 16, and Matthew Hollander, 13, who both attended Sydney’s prestigious Knox Grammar School in Wahroonga.

Julie Richards, 47, and her daughter Jessica, 20, from Brisbane, are also among Australian tourists who were killed.

Prime Minister Scott Morrison has said 10 Australians are "missing and presumed deceased" but it's unclear how many of those might overlap with the eight deaths already confirmed by family and friends.

The tour group watches on in horror as the island erupts. Source: YouTube/ Allessandro Kauffmann

"In the days ahead, there will be worse news," he warned on Thursday.

The volcano remains volatile, amid fears another large explosion is imminent, but New Zealand police have announced they will attempt to retrieve eight bodies from the island on Friday morning.

"We know that with quite a number of persons still on the island, understood to be deceased, that we will just have to be patient while circumstances are continually reviewed," Mr Morrison said earlier.

When the recovery occurs, "there will be the very grim task of identification".

Five injured Australians have been flown home, with seven more to follow in the next 24 hours, leaving just one Australian in a New Zealand hospital.

Skin grafts needed for survivors

Sixteen people are confirmed dead from the volcano blast. Source: AAP

Those who have survived are in desperate need of skin grafts.

Dr Peter Watson, a chief medical officer, said at a press conference that they had needed to order extra skin from American skin banks.

Dr Watson said staff anticipated needing an extra 120sqm of skin for grafts for patients. Most of those who survived the eruption at White Island on Monday suffered burns, and 28 patients remain hospitalised, including 23 in critical condition.

With The Associated Press and AAP

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