Police have revealed more details in the hunt for the killer of a woman whose body was fished from the water at a Gulf Harbour marina inside rubbish bags.

Acting Detective Inspector Tim Williams said a post-mortem examination of the body found in the harbour has been completed.

Police have not yet been able to identify the victim, other than the body was a female and middle-aged. The height of the body is about 160cm.

Williams dismissed any speculation the woman was Yanfei Bao, a real estate agent who went missing in Christchurch on July 19 last year.

But police have today released pictures of blue pyjama bottoms with a pattern on them and an emblem of a singlet she was wearing when she was found.

Acting Detective Inspector Tim Williams. Photo / Jason Oxenham 

Williams confirmed Interpol was involved in the investigation in a bid to identify her.

“We’re asking any member of the public who recognises this description of this woman to come forward to police,” Williams said.

“She might be someone’s mother, or sister or grandmother.”

Once police identified the body, they would then tell her next of kin of her death, he said.

• Body in bag mystery: Person identified as small Asian woman
• 'A hand sticking out': Fisherman finds body in plastic bag, police seek identity
• Witnesses say they may have seen body in Gulf Harbour water a day earlier

Police investigating the murder of an Asian woman whose body was found at Gulf Harbour have released this image of the pyjama pants she was wearing when found. Photo / NZ Police 

Police investigating the murder of an Asian woman whose body was found at Gulf Harbour have released this photo of branding on a singlet found on the body. Photo / NZ Police 

“The Government is committed to keeping all New Zealanders safe and secure.”

He said the investigation was complex, as police were still trying to work out why, when and where she died.

“We’re continuing to treat this matter very seriously and we’re determined to hold the person or persons accountable for this death.

There was no wider risk to the public, he said.

“If there’s a woman in your community who matches this description that you haven’t seen for a while or have concerns about, please make contact with the investigation team.

He said people had already come forward with CCTV footage and other information.

She was wrapped in black plastic clean sacks, Williams said.

He would not speculate on whether the offender remained in the country.

“We’re keeping an open mind to all avenues of the investigation,” he said.

“She was wrapped in black plastic clean sacks. But I won’t go into any more detail at this stage.

“We are dedicated to finding out what happened to this lady.

He said Chinese-speaking police officers were integral to their investigation.

On any potential risk to the wider public, Williams said he was confident it was an isolated incident.

There would be a large police presence around Whangaparāoa in the coming days.

Police were talking to New Zealand-Chinese media organisations to help their investigation.

“It is complex because we don’t know who she is,” Williams said.

Photo / Michael Craig 

Police yesterday said the person found floating inside black bags near the shoreline of Gulf Harbour Marina was a small woman of Asian descent.

The discovery of the body was initially treated as unexplained before police upgraded it to a homicide investigation.

Police appealed for information about the mystery woman and asked anyone who had been in the area in recent days and may have seen something to come forward.

Police at Gulf Harbour after a body was found in a bag on Tuesday. Photo / RNZ / Nick Monro 

Yesterday, Williams said police were still unsure of the circumstances surrounding the woman’s death and would not speculate.

“At this stage, we have not been able to confirm the identity of the victim, but we can say they are a female of Asian descent, possibly Chinese, and small in stature.

“Police are asking anyone who may have information on a woman matching the description who they have concerns for to please get in touch.

“Our priority will be to then identify and notify the victim’s next of kin.”

Police were called to a reserve in the northern end of Auckland on Tuesday afternoon after the body was found by fisherman Paul Middleton.

Fisherman Paul Middleton talking to police after fishing out human remains wrapped in plastic bags in Gulf Harbour. Photo / RNZ / Nick Monro 

Middleton described how he saw something large floating in the water.

“I [cast] my lure out ... and nothing much was happening, but there was a bag out there,” he told RNZ on Tuesday.

At the time, he did not know it was a bag and thought it was a log or a dead animal.

He hooked it and pulled it into the shore - it was heavy but he managed to pull it up the rocks a little.

“I took the hook out and thought, ‘Right, let’s see if it’s a bag of rubbish and I need to dump it in a rubbish bin or something’.”

There was “a bit of clothing ... and then there was this hand sticking out”.

It was at that point that he called police.

“Two cops turned up and they thought I’d actually said there’s just a hand in a bag and then they went down there and went, ‘Oh no we’ve got a body’,” Middleton said.

Tourists parked in a camper van at Gulf Harbour said they noticed something large floating in the water a day before the body was found. The couple said they had looked at the object from the shoreline but hadn’t known what it was.

• Police have urged anyone with information to contact police on 105 or go online using the ‘update my report’ function and use reference file number 240312/9837. Alternatively, information can be provided anonymously via Crime Stoppers on 0800 555 111. 
• The community can contact police on 0800 755 021 to speak directly to the investigation team.