The search for Steven Bailey, who went missing almost a week ago, has been called off by South Australian Police.
The 62-year-old was last seen at his workplace in the Adelaide Hills on Friday.
His gold Hyundai Elantra was then found on Sunday, abandoned on the West Boundary Track of Ngarkart Conservation Park, about three hours drive away from his workplace.
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A large scale search was then launched, with local SES personnel using thermal imaging devices and drones to search several square kilometres of scrub.
The multi-agency search has now been called off.
Ngarkat is 271,000ha in size, making it the largest patch of remnant native vegetation in settled agricultural South Australia.
The park has a number of remote tracks and 10 different walking trails through a vast mallee landscape.
Bailey is from the regional town of Mypolonga on the River Murray and is well-known in the area.
He previously taught boxing out of his shed.
A Murray Bridge local remembered him years after he finished training with Bailey.
“He was a good sort, never charged us for his training,” he told 7NEWS.com.au.
Steven Bailey has been missing since February 28, with concerns for his welfare. Credit: SAPOL Another search is not out of the question, SA Police Superintendent Cynthia Healey said.
“The efforts of those involved in the search over the past week have been exhaustive,” Healey said.
“The terrain we have been searching has been dense and difficult to search.
“I’d like to thank the SES volunteers, as well as the police resources, who travelled to assist our local resources.
“I am certain that all of the area accessible to the search team by air and foot has been searched.
“However, I won’t rule out the possibility of searching this area again if further information is provided which hasn’t been available to us at this time.”
The Ngarkat Conservation Park is extremely remote near the Victorian boarder. Credit: Google Maps Police and family still have concerns for Bailey’s welfare.
Community members are urged to keep an eye out for Bailey, who is described as having a slim build with grey hair and a goatee.
He was last seen wearing a beige t-shirt, long pants and one thong.
Anyone who spots him or has information on his whereabouts should contact the police assistance line immediately on 131 444, and quote reference number 59133.