Manurewa mother Arishma Archana Singh likely knew her killer and allowed them into her home, police say.
Detective Inspector Gary Lendrum is addressing the Herald and other media about the death of 24-year-old childcare worker Arishma Archana Singh yesterday.
Police say Singh had "obvious injuries".
The post mortem is taking place today.
Police say there is no sign of forced entry and they do not believe it was a random attack.
Lendrum said police were following lines of inquiry.
"We are quite determined to get to the bottom of this," he said.
A large team of officers were working on the case.
Lendrum said his "gut feeling" is that Singh knew her killer and allowed them into her home.
There was no sign of forced entry.
Her ex-husband has spoken to police - along with other relatives.
Singh has a new partner and was with him in the hours before she died.
Lendrum said the boyfriend left about 20 minutes before Singh's parents came home and found her dead.
He said the boyfriend was being cooperative.
Police were collecting CCTV footage from the area and said they would be "trawling through it".
Lendrum confirmed Singh's daughter was not at the house when she died. She was with her father, as per a pre arranged custody agreement.
He said he was "very" happy with the cooperation from Singh's family.
He said she came home from a friend's birthday party with her boyfriend at 12.45am.
Singh rang her parents soon after as she believed she could hear someone outside the house.
They came straight home - and found her dead.
Singh did not tell her parents what she could hear and "didn't articulate" why she was scared.
Lendrum said part of the investigation was looking into any family harm issues Singh may have had.
He said he will be checking Singh's phone as part of the investigation.
Lendrum said it was known to police where Singh's boyfriend went and what he was doing after he left Maich Rd.
He would not comment further on that.
"The answer is much closer to home."
Lendrum assured the community that they did not have to worry about a killer "wandering around" the streets.
Singh, also known as Archana Chand, was found by her parents lying on the floor of her bedroom "in a pool of blood" in the early hours of the morning.
Police launched a homicide investigation soon after.
The young mum lived at the Maich Rd house with her parents and 3-year-old daughter.
She had been out to a friend's birthday party and it appears she was killed soon after she arrived home.
Her parents, Rakesh and Aradhana Singh, had also been out visiting relatives and found her body when they returned.
A source said that when her parents got home they found the main door unlocked.
"When they went in her room they found her on the floor in a pool of blood," the source said.
"She had injuries to her face and body."
The source said police initially told Singh's family they suspected she had come home and interrupted an intruder or burglar.
Singh's body was removed from the house yesterday and a post-mortem examination was carried out.
Lendrum said he hoped to have more answers about the circumstances of her death after that examination.
Yesterday Lendrum said it was "unclear" what had gone on in Singh's house before she died.
A scene examination with specialist forensic staff continues today.
Police would like to hear from any members of the community who may have been in the
Maich Rd area of Manurewa last night.
Any witnesses should contact the Counties Manukau Police on 09 261 1321.
To pass information to police anonymously, they could call Crimestoppers anonymously on 0800 555 111.
It's understood a NZDF aircraft and multiple helicopters are involved.