Notorious killer Stephen Williams has been sentenced to preventive detention with a minimum of 14 years in prison for trying to kill an inmate at Rimutaka Prison.
At sentencing in the High Court in Wellington on Friday, he threatened to kill media and told the judge to "hurry up".
Williams told a cameraperson: "F**king stare me down and I'll f**king kill you".
He is already serving a life sentence for bashing his girlfriend's six-year-old daughter Coral-Ellen Burrows to death during a P-fuelled rage in Featherston in 2003.
"The defendant sharpened a plastic knife using the blade from a pencil sharpener and wrapped the handle in brown towelling material," the latest police summary of facts says.
Williams then walked to the victim's cell and threw boiling water over the victim, according to the summary of facts.
"While the victim was affected by the boiling water the defendant began striking him in the neck area with the sharpened knife."
Justice Peter Churchman said Williams had shared his intentions to kill again.
"The sentence of preventive detention, which I find must be imposed, means you will never be released until you are no longer a threat to the community's safety."