He says at the moment they're focusing on identifying the woman, and as she is unable to speak to police, witnesses will be crucial in solving the case.
The woman is described as being in her 20s to 30s, Caucasian, with short dark hair, and has a distinctive tattoo of a rose with the words mum and dad written through it.
Police have released a photograph of the tattoo on her left calf.
The tattoo is of a cross with a rose, and has the words 'mum' and 'dad'.
A Waiwhiu Rd resident said there was a heavy police presence on the street, with "a lot of cop cars" visible.
A worker at Top Of The Dome Cafe said a tent had been erected about a kilometre up Waiwhiu Rd on the right hand side of the road.
Rodney area commander, Inspector Mark Fergus, said anyone who may know who this woman is needs to contact Police.
"We want to assure the public we are doing everything we can to identify the victim and to establish what has happened. We urge anyone who has any information that can assist police to please get in touch.
"If anyone has information to assist the investigation team, we ask that they contact detective senior sergeant Kim Libby at Orewa Police Station on 09 426 4555.
"Alternatively you contact Crimestoppers anonymously on 0800 555 111."
