An elderly man who went missing four days ago is in "good spirits" after being found alive in bushland in Sydney's north.
Ronald Weaver, who suffers from Alzheimer's and other medical conditions, was last seen on Woolcott Avenue in Wahroonga at 10am on Tuesday, sparking a full-scale search of up to 100 emergency service workers.
The 79-year-old was found by New South Wales State Emergency Service (SES) in North Wahroonga bushland about 11.30am today.
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Acting Superintendent Carlene Mahony said he was found in "very dense" bushland just off Jubes Mountain Bike Park near a tree.
"He was in good spirits and could respond to his name and he was showing signs of being able to hold rescuer's hands at the time," Mahony said.
Weaver was found in an area that had already been searched.
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"We presume that he has moved around this area and he has been in that tree or near that tree for probably the last 24 hours.
"We were very happy for the family and it was fantastic for us to be able to go and get Hannah his wife and take her down to the scene today.
"It was really nice and amazing to see her reunite with him and he did recognise her when she came down to the scene."
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She said everyone was surprised to see him alive as Weaver had survived four days without any access to food or water.
NSW SES volunteer Andy Kalsey found Weaver after he'd been searching with crews all morning.
"There was a team of eight of us and we were spread out in a line abreast," Kalsey said.
"It was my job to come up to the ridge and I just saw him out of the corner of my eye.
"When I got to talk to him and when I said 'g'day mate how you going' he was quite lucid."
Kalsey said he was relieved when he realised people had been searching for him.
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The local SES described the area as very rocky, with many cliffs, creeks and snakes.
Weaver is currently at Sydney's Royal North Shore hospital in a stable condition, where he is getting some treatment and "much-needed rest".
The four-day coordinated effort involved NSW Police resources including PolAir, the dog squad and trail bike unit as well as NSW SES, NSW Rural Fire Service and the National Parks and Wildlife Service assisted in the four-day land and air search.
Source: 9News