It's been a month since the body the woman was found by a fisherman wrapped in plastic bags and her identity is still unknown.
The woman has been described as middle-aged, of Chinese descent and "small in stature", by police.
She was wearing blue pyjama bottoms with a pattern, and a light-coloured singlet with an emblem when she was found.
"Our team are also engaging with a number of NZ police liaison officers in regards to this matter."
Williams said the investigation was "complex" and he understood the community had many questions that police were working to answer.
"Police will continue to provide further updates as our investigation allows."
The community can contact police on 0800 755 021 to speak directly to the investigation team with any information.