The search for missing Torbay woman Pat Wearn has been suspended.
Wearn, 73, who suffers from Alzheimer's, hasn't been seen since she left her Caversham Drive home last Monday, to go for a regular walk.
Hundreds of police, LandSAR, Navy, Airforce, Civil Defence and Fire Service personnel have searched properties, reserves and bush areas in the Torbay, Browns Bay and Long Bay areas over the past week, but there has been no sign of her.
Members of the Police National Dive Squad travelled from Wellington and searched several waterways and ponds in the Torbay area.
Police have consulted with medical experts who have expertise in survival and "sadly the time period in which Mrs Wearn could be expected to survive has been well passed", said Inspector Claire Humble, Waitemata police.
"Sadly have reached the point where we have no further information that would allow us to continue with the search operation to find Mrs Wearn. If we receive any new information that would enable us to search further we will certainly assess it and where possible, look to act on it."
Humble said the decision to suspend a search was a formal process that was peer-reviewed to ensure all possible search options had been exhausted.
"Whilst the land-based search has been suspended, our enquiry and investigation phase continues. As well as the search and rescue operation, over the past week we have also had a team of police officers making enquiries, following up on all reported sightings of people fitting Mrs Wearn's description, any information provided to Police as part of the area canvass.
"They are also reviewing hundreds of hours of CCTV footage taken from dozens of cameras around the area, over the past week. This team will continue their investigation phase."
Wearn's family had been advised of the decision to formally suspend the search. Humble said they were understanding of the decision and continue to be supported by police, friends and family, and the Torbay community.
Police are still encouraging anyone returning home from holiday to search their properties, especially any areas where someone could try to seek shelter.
Anyone with information is asked to contact police immediately.