Detectives on Renee Duckmanton staying tight-lipped

Detectives hunting Renee Duckmanton's killer are keeping tight-lipped on whether they have any leads or suspects, 12 days since she was last seen in Christchurch's red light district.

A large team of police officers and specialist staff are dedicated to finding out how Miss Duckmanton's body came to be burned and dumped on a rural Canterbury road, 60km from where she was last seen.

Police yesterday released the last known image of the 22-year-old sex worker walking near the intersection of Manchester and Peterborough streets, where prostitutes operate at night, at about 9pm on Saturday, May 14 - almost 24 hours before her body was found.

Police say they can't rule out a client being behind her killing.

Miss Duckmanton's home in Cashmere, and mother Tracy's Housing New Zealand house at nearby Kowhai Tce, St Martins, were the focus of intense forensic scrutiny last week.

But police refuse to say what they found at either address. No other locations have been examined as part of inquiries.

Asked if police yet know how or where Miss Duckmanton was killed, a spokeswoman replied: "Both of these still remain an important part of our investigation".

She said police are following "a number of lines of enquiries" and "continue to speak with a number of people who may have information".

Police refuse to say if they have any suspects or if anyone has been tested for DNA links to the case.

"Police are conducting a number of lines of enquiries, however, as the investigation is ongoing, police are not able to discuss these further," the spokeswoman added.

Although TV crime shows like CSI suggest the first 48 hours is critical to finding the killer, Victoria University Criminologist Dr Trevor Bradley said it doesn't work like that in reality.

Forensic examinations can take weeks in New Zealand and "patience is key", he said.

"I'm not surprised that there hasn't been any major breakthroughs, or at least, that police haven't announced any," he said.

"They might be quite carefully building up a case about some suspect, and of course they wouldn't be telling anybody about that."

If they have a suspect, they could be quietly monitoring them and paying attention to digital communications and social media, Dr Bradley said.

Most homicides in New Zealand are 'name and address' murders, involving spouses or people who know each other.

Stranger-related crimes can take detectives much longer to solve.

Officers will be talking to Miss Duckmanton's family, friends, work colleagues, and others in the sex industry, Dr Bradley said.

"They will be asking for details of any dodgy clients and seeing if they fit what would be a pretty standard profile of a person who would commit this type of offence."

Miss Duckmanton was laid to rest in Christchurch on Monday.

Police say they remain in contact with her devastated family, who have described her as a "really bubbly, really happy, lovely girl".