Child-killer Stephen Williams allegedly attacks fellow inmate at Rimutaka

Stephen Williams allegedly assaulted another prisoner at Rimutaka Prison on Wednesday. Photo / File

The man who murdered 6-year-old Coral-Ellen Burrows 16 years ago has been placed in a high-security unit after stabbing and pouring "prison napalm" on another inmate.

Stephen Williams is serving a life sentence for murder after he beat the Featherston schoolgirl to death while high on methamphetamine in September 2003, then dumped her body by Lake Onoke (Ferry) in Wairarapa.

He is also in preventive detention following the attempted murder of a prisoner at Paremoremo in 2016.

But Stuff reported he had been moved to a low-security area in Rimutaka Prison, where on Wednesdayhe allegedly poured "prison napalm" - a combination of boiling water and sugar - over another prisoner, then stabbed them multiple times.

Police confirmed to the Herald they were investigating an assault on a prisoner that had occurred at Rimutaka Prison on July 31.

Inquiries into the assault were ongoing and no charges had been laid as yet, a police spokeswoman said.

Rimutaka and Arohata prisons director Viv Whelan confirmed the alleged perpetrator of the assault is Steven Williams.

"I completely appreciate that hearing about incidents like this may be hugely distressing for victims, and I apologise for that," Whelan said.

"We're carrying out a full review into the incident, which will include the circumstances of the assault and what led to it, and whether Mr Williams' security classification and unit placement were appropriate.

"Mr Williams is being managed as a maximum-security prisoner. He is on directed segregation in the prison's management unit and is likely to be moved to maximum security Auckland Prison once police have completed their investigation."

Coral's father Ron Burrows told the Herald it was like "Groundhog Day" hearing of yet another attack by Williams.

Storm Burrows (left) and Ron Burrows, brother and father of Coral Burrows, pictured at home in the Waikato in 2015. Photo / Doug Sherring

Burrows was on the victims' register but said he had not been told Williams had been put in a low security part of the prison.

He was fuming to hear through the media that there had been yet another alleged assault by his daughter's killer.

"He's a coward and he's scared of what will happen to him when he gets out," Burrows said - though he hastened to add he had never threatened Williams.

"I'm sick of this crap. He has been in three different low security prisons and severely hurt people," he wrote on social media.

"When will Corrections learn. His track record speaks for itself.

"I was told he was given preventive detention last time. He is a coward who only attacks people who can't fight back."

Burrows told the Herald he was tired of hearing Williams' name and seeing his face.

He wanted to dwell on positive things that had happened since Coral's death - like the call he had received recently from a group that cleans up the shores of Lake Onoke.

The group planned to install a bench in Coral's honour and had asked what he would like the inscription to say.

Coral Burrows was murdered in 2003. A seat is to be installed and inscribed in her honour on the shores of Lake Onoke where her body was found. Photo / File

"I said well really I'll leave it up to you guys. But when they do put it up I might go down there," Burrows said. It was a "lovely" gesture, he added.

Stephen Williams "intends to continue harming others"

Whelan said the prisoner attacked by Williams remains in hospital and his injuries were not considered life-threatening.

Williams has claimed in the past that he would continue to attempt to hurt other people to ensure he was never made eligible for parole.

In December 2016 Williams tried to murder another prisoner by stabbing him with a fluorescent lightbulb and a broom handle during a tattooing session in Auckland Prison at Paremoremo.

But his victim, convicted murderer Nikki Roper, survived. Williams pleaded guilty to attempted murder and was sentenced to preventive detention, on top of his existing life sentence for the murder of Coral Burrows.

That was his 97th conviction, according to a statement from Crown prosecutor Scott McColgan in 2017.

Stephen Williams, killer of Coral Burrows, at his sentencing in 2017 for the attempted murder of another inmate at Paremoremo prison. Photo / Michael Craig

Health assessors at the time said Williams posed a serious danger to others and would likely intend to commit serious violent offences in the future, McColgan told the court.

"Indeed he has been very clear that he intends to continue harming others until he receives the sentence he should have got for his original murder conviction."

Stuff reported Williams had been moved to a high-security unit following Wednesday's attack.