KEY POINTS:
Two people were seen walking up and down the drive way of Manurewa home invasion victim Yin Ping Yang for about a month before she was attacked.
The 80-year-old grandmother died in hospital on June 14, three days after she was left unconscious in the bedroom of her
family home following a vicious beating.
Detective John Clark said one man was seen on her driveway was wearing a black sweatshirt with the number 89 in blue on the back while another had a distinctive Maori or Pacific tattoo across his neck, upper arm and chest.
Mr Clark said one of the men was also seen wearing bandanna.
"We couldn't say that it is related to a particular youth gang or anything like that," he said.
Detective Inspector Mark Gutrie said in the past two weeks police had spoken to 2000 people at about 680 homes. He said up to 80 people had reported suspicious people in the area.
Mr Clark said Manurewa residents had told police that they had spotted suspicious people on their property.
He said the people, when approached, had given excuses such as: "my car has broken down, can I use your phone? I've run out of petrol, do you have any petrol I can have?"
He said there were also reports of people posing as door-to-door salesmen and carpet cleaners.
Mr Clark said he believed these people were casing the houses.
He said residents had also been asked if they were the only person living at the address, what time they went to work and what their phone number was.
Mr Gutrie said police had information that one person was in the house at the time of the killing but another could have been waiting outside or in a getaway car.
"We're still waiting for all the forensic evidence to come back. We've cleared most of the finger prints in the house, although there are still a couple of family members that we need to get elimination finger prints off," Mr Gutrie said.
He said police had all but ruled out a sexual motive.
Mr Gutrie said the owners of the property owned their own business and the offenders could have been looking for cash.
He described the assault on Mrs Yang as vicious and said the offender could have had blood on them when they left the house.
- NZHERALD STAFF