Police have this morning released further details about the deaths of Fuk-Fu Joseph Kwok and Mei Han Chong, saying their murders are "beyond comprehension" for the family.
Two people have been arrested and charged with the murder of the Auckland couple.
Kwok's body was found in their Ellerslie home on Monday. He had been stabbed several times.
Chong's body was found in the early hours of Friday morning in the Greenhithe area, and police confirmed more details about her death on Sunday.
Detective Inspector Scott Beard said the post-mortem completed on Friday found she died from blunt force injuries to her head.
"This news is understandably distressing to her family, in particular Mei and Joseph's son. Mei was a 5-foot-tall, 67-year-old woman, weighing no more than 45 kilograms.
"It is beyond comprehension for the family as to how something like this could happen to Mei and Joseph."
Beard said the investigation had been "fast-moving", involving numerous scenes across a large part of Auckland.
"In recent days, police have executed search warrants at a number of addresses and seized two vehicles we believe are linked to the murders."
He said CCTV footage had been used to identify the suspicious activity of a vehicle and two people around the scene in Celtic Crescent between 1.08am and 3.47am on Sunday 5 November, including the victim's car leaving the address at 3.47am.
"Police now know the two vehicles, including the stolen family car were together driving around the Ellerslie area for some time, and ask if anyone saw them to please contact police."
Beard said police still wanted to want to hear from anyone who saw suspicious activity or the victims' blue Kia Rio car around Kereru Grove in Greenhithe or Hall Road in Glenfield, any time between the early hours of Sunday and Thursday.
"When police recovered the Kia Rio, it was displaying different number plates to what should have been on the car.
"The number plates start with the letters MDM. If this registers with you, or you have CCTV footage of a blue Kia Rio displaying these plates in timeframe mentioned, please contact us."
Police also revealed further details about the lives of the victims.
They moved to New Zealand from Hong Kong in 1988. They both had multiple siblings, including two who also live in New Zealand
Chong had been a nurse before becoming a midwife and was a supportive mother to her and Joseph's son - their only child.
"When Mei came to New Zealand she felt the language barrier would be an issue for her as a nurse, so focused on her family.
This including supporting her son as he too began a career in medicine."
Beard said while she was very small in stature, she was "strong-minded and passionate about issues that were dear to her".
Kwok was an orthopaedic nurse for many years and was "happy in his own world" and cared about supporting his family and doing a good job.
"He was still working incredibly hard, and got home from work at 11.30pm the night before he was murdered.
"Joseph and Mei were a loving couple whose careers involved helping other people.
"Our thoughts are with them and their grieving family."