The possibility that a woman killed Marton pensioner Mona Morriss hasn't been ruled out by police, who are examining exhibits with fingerprints on them.
Inquiry head Detective Sergeant Tim Smith, who leads the Operation Wellington investigation, said yesterday he was keeping an open mind on the gender of the killerand the weapon used.
"We're looking for a sharp instrument, similar to a knife," he said.
Forensics results on items that included several knives handed to police in a town-wide canvass weren't available yet, but Mr Smith said he wouldn't be commenting on them anyway.
"They're still analysing exhibits with fingerprints. It's not like CSI, where it gets done in 24 hours.
"I'm expecting, with the homicide investigation in Wanganui at a prosecution level, the ESR scientists will have more time to spend on our analysis," he said.
Operation Wellington, which involves 25 investigators, was working its way through a list of "persons of interest".
"We're working through the list and are ... about a third of the way through," he said.
They had no evidence to suggest the killer was still in Marton, but Mr Smith remained convinced the killer knew the Rangitikei town well.
He couldn't comment on the likelihood of such a crime being repeated.
"This was a shocking, disturbing crime and I'd hope the person wouldn't want to do that again."
Mr Smith said it was one of the worst crimes he'd encountered in his career.
Mr Smith distanced police from a Sensible Sentencing Trust idea to post a reward for more information.
"If they want to talk about that they can. It's not an area that we're looking at yet," he said.
"The answer could be in the information we already have.
"I'd like to think the public are horrified by this disgusting killing enough to come forward without money being the motivating factor," he said.
