The search for Hamilton man Raymond Stirling has been suspended.
Stirling hasn't been seen since January 15 when he was dropped off at his Halcione Cl, Flagstaff, home after a week at the beach.
He was reported missing the following day- his 84th birthday- which he was due to spend with family for a celebratory dinner.
Stirling has mild dementia and hundreds of family and locals have helped search for the great-grandfather, including scouring the Waikato River.
On Friday afternoon Waikato search and rescue's Sergeant Vince Ranger said the search would now be called off.
"Police would like to thank LandSar, Raymond's family and friends, and everyone else who volunteered in the search for their support, time and effort," he said.
"Raymond's family have been notified and our thoughts are with them at this difficult time."
The disappearance has been referred to the coroner and police would continue to follow up any further information if it came to them.
One of Stirling's five children, daughter Julie Caddigan, said the family still hoped to find him and would continue searching.
She believed up to 1000 people had volunteered to help find her father, and the family was blown away by the support from the Hamilton community who had donated petrol, time and food.
"We're not scaling back [the search], we're picking up again," she said.
"Please keep looking. We definitely have to find him."
Stirling, known as "Curly" to his friends is described as of slim build, and often carries a walking stick.
He was known to hitch hike and was most likely wearing white sneakers with red stripes, and navy blue trackpants.
Caddigan asked Hamilton residents to check their backyards thoroughly, looking "over, in an under everything".
"We'd just like to say a huge thank you [to the community]. It's given us huge faith in our local community."