The former detective sergeant who arrested Jules Mikus for the murder of Napier schoolgirl Teresa Cormack says he "despises" the killer and won't mourn his passing.
Corrections has confirmed Mikus - who had brain cancer - died in Rimutaka Prison on Friday.
Mikus abducted and raped 6-year-old Teresa Cormack, who was found shallow grave at Whirinaki Beach eight days after she went missing in June 1987.
He was able to avoid arrest until advances in DNA technology caught up with him in 2002.
Keith Price, now a Napier City councillor, said interviewed Mikus at the time of his arrest.
"I mean I don't wish death on anyone but he was a pretty horrible man and I don't really have a lot of time for him. What he did was horrible," Mr Price said.
"He was a horrible cold man. A very, very calculated, non-emotional, cold [man] and he just denied doing anything. I don't think you get much more cold than he was."
Mr Price said he had hoped Mikus would be more forthcoming in police interviews.
"I would have like him to tell us all about it and admitted to it but he was just hard work. Really hard work."
"I actually despise the man, absolutely despise him."
Mr Price said Mikus had always been a person of interest, but a case couldn't be made against him.
"He just denied it and we didn't have enough to charge him with his denial but then when we had the DNA profile we had plenty.
"I was working when she [Teresa] initially when missing and then I was involved in the termination of it. We did taking blood off suspects for about six months and then when his went into the system that was it."
He said the case would stay with him forever.
"It's something you think of. I'm just so pleased we caught him and once we caught him he's never been out. He's never had any freedom."
Mr Price, who had children of his own at the time, said Teresa Cormack's murder had change the way society thought about letting their children walk to school.
"I think it was a turning point about people feeling comfortable about their children walking the streets. It was a real turning point. People were pretty shocked I mean your kids just walked to school back in those days and all of a sudden you didn't feel comfortable with children walking to school or being out on the streets."
Mr Price said it would be a difficult time for Teresa's mother Kelly Pigott.
"I don't think she'd ever get over what she's been through and I guess it brings it back to her again."
Mikus had been denied parole several times, most recently in April 2016.
Corrections said Mikus's death was not being treated as suspicious and that police had been advised and were notifying his next of kin.
It said all deaths in custody were referred to the Coroner and the independent Corrections Inspectorate would also investigate the death.
While the death remained subject to investigation Corrections said it was limited in what else it could say.