A survivor of the Whakaari/White Island eruption, who lost her sister and father, says more people would have survived if help came sooner.
Australian woman Stephanie Browitt, 23, suffered burns to 70 per cent of her body and lost parts of her fingers as a result of the December 9 eruption.
The volcano has been in a state of unrest since it erupted last year, killing 21 people and injuring 26, with scientists saying it could blow again with little warning.
Browitt's younger sister Krystal, 21, and father Paul were among those who died as a result of the eruption.
The 23-year-old was one of 12 people rescued by a group of local helicopter tour pilots who flew to the island after it had blown-up.
"I'm upset at the whole situation, but I'm very angry that it took so long for the rescue to come," Browitt told Four Corners.
"Now I realise rescue actually wasn't coming. It was just three pilots who chose to risk their own lives to help us and if they hadn't come, we'd all be gone.
"I know that if help had come sooner, there would probably be more people alive from our group."
Following the eruption, authorities did not send official rescue helicopter to the volcano immediately, instead, they were sent to Whakatāne, around 50km away.
The family only learnt about the risk of eruption once they were on the island, Browitt said.
The Browitts were part of a group of 38 people from the Ovation of the Seas cruise ship who were on a day trip to Whakaari/White Island.
Browitt's mother Marie decided to stay on the ship docked in Tauranga, Bay of Plenty.
White Island Tours guides only told the group the volcano was at alert level two, the highest it could be before an eruption occurs, once they were on the island, Browitt said.
"Once you're on the island, you can't get back off," she said.
"I was a little concerned ... but at the same time you sort of have trust that we wouldn't be on here, they wouldn't be running tours if they thought it was dangerous."
The Browitts reached the centre of the island at about 2pm, taking a picture together at the edge of the steaming crater lake at 2.04pm.
Six minutes afterwards as they were headed to the jetty when Whakaari/White island erupted.
Browitt's younger sister Krystal managed to capture the moment it began on camera, with a gas cloud beginning to emerge from near the crater lake.
Their tour guide instructed the group to start running and before Browitt was able to put her gas mask on her face she was hit by a wave of ash and rock.
"It felt like a wave, like it just takes you," she said.
"I was just knocked over. I was tumbling, rolling, for minutes. I mean it felt like forever until it stopped and then it was just burning hot.
"I remember trying to stand up and it took so much energy just to stand up I remember thinking, 'I can't believe how hard this is'. My legs just felt like jelly."
After getting to her feet and walking for a short time, Browitt fell and tumbled down a small hill and landed among a group of people.
Help only arrived nearly an hour after the volcano erupted.
Browitt and her father and Paul were flown to Melbourne and Paul died in hospital four weeks after the eruption.
The Browitt family do not know what happened to Krystal and whether she was brought back on one of the helicopters on December 9 or if her body was one of six left on the island and recovered four days later.
The family did not sign any waivers or get any receipts from the cruise ship operator, Royal Caribbean, about the volcano tour.
And they were not told about the risks either, Browitt said.
"If we were informed of the level and that there was a lot of [volcanic] activity in the coming weeks leading up to it ... we wouldn't have done it," she said.
A group of passengers and victims' relatives are now taking legal action against the cruise ship operator.