The incident has prompted a reminder from a senior district council official that people need to take extra care in active geothermal areas and stay well clear.
Anna Kare said she was showing her mother-in-law from France some of Rotorua's sights when she heard someone screaming "my hands, my hands".
She then watched as a teenage boy ran to his parents carrying what looked to be his younger brother on his back.
"The boy was yelling 'my hands, my hands' and I saw all the skin on his hands peeling off.
"I then saw the burns were all the way from his head to his feet.
"There was no mud on him so I don't think he fell into a mud pool, it was just water."
Mrs Kare said other witnesses started pouring water all over the boy's body.
"Oh my goodness, there was screaming and yelling - it was just horrible," she told The Daily Post.
"He would say 'my feet, my feet', then after the water he was saying 'my face, my face' then back to his hands again.
"My daughter was crying for hours ... she has already had nightmares about it."
Mrs Kare said the boy's family called an ambulance and shortly afterward St John staff were taking him to hospital.
"We didn't see how it happened but his family were trying to calm him down. He was in a lot of pain ... it was very traumatic. I hope he will be okay," she said.
It is not known which of the hot pools the boy fell into. However, Rotorua District Council Parks and Recreation manager Garry Page said all the hot pools in Kuirau Park were fenced off, with warning signs in place.
"There are few pools without mud so [if witnesses say he didn't have mud on him] he could have fallen into a part of the big lake [in the park] that can get very hot, but I'm not sure at this stage.
"There are signs all over the park warning people of the pools' dangerous geothermal nature and we have made every attempt to keep people out of them.
"We have cut sight lines so people can see into them but they still climb over the fences and put themselves at risk."
Mr Page said some of the pools in Kuirau Park could reach temperatures of about 100C, boiling point.
But he said hot pool accidents were not a common occurrence.
"As far as I can remember, the only times people have been hurt in the last 20 years or so were when people went beyond the safety barriers."
Mr Page said he would urge people to contact the council if they saw any holes or damage to any safety barriers around hot pools so they could be repaired.
"It's no use telling us about it afterwards," he said.
- Rotorua Daily Post, NZ Herald staff
