THE search for missing 79-year-old Neilborough man Bruce Evans is scaling back for the evening.
Police and SES will be patrolling the Neilborough and Raywood areas.
Residents should expect lights and sirens to be activated intermittently during patrols, as investigators understand Mr Evans might be attracted to emergency lights.
People might also see the police Airwing in the skies above the search area.
The Airwing will be using its thermal imaging camera.
"We are asking residents not to come out of their addresses if they hear the chopper as this will make it difficult for police to pinpoint the missing man's heat signature," police said in a statement.
Victoria Police inspector Troy Hargadon said search parties are remaining positive they will find Bruce Evans safe and well.
The 79-year-old Neilborough man was last seen on Tuesday evening before being reported missing on Wednesday morning.
"He lives with family and the circumstance around him not being at home are being investigated but there is nothing to say it's suspicious," Inspector Hargadon said. "We think it is a misadventure. He is an elderly gentleman with dementia and we think it's a scenario where he has gone for a walk and unfortunately failed to return.
"Part of the the (investigation) process is establishing when Mr Evans has takent that walk. He was last seen on Tuesday evening and reported missing to police the following day.
"We would strongly encourage anyone who has seen him walking or offered him a lift to report to local police at Bendigo or call CrimeStoppers."
Inspector Hargadon said more than 100 people from different agencies are assisting with the search which currently encompasses a nine kilometre radius from Mr Evans' home in Reillys Road.
"We are supported strongly by specialist units from Melbourne, search and rescue, the mounted branch, air wing, canine units and services from other organisations such as Parks Victoria, SES and the CFA. Some people have also volunteered.
"There are concerns around terrain, which is bordering a national park, and some mine activity from previous generations. There are also risks and circumstances we need to consider when deploying our staff.
"Certainly, there are significant concerns around the wellbeing of Mr Evans. He is an elderly man with dementia and it has been cold. All considerations need to be taken into account but every effort at this point is in locating Mr Evans safe and well.
"There are a lot of variables in everything we do but are working to a guide of a safe and wonderful outcome in finding Mr Evans safe and well."
POLICE Airwing and Dog Squad have been called in to help search for missing Neilborough man Bruce Evans.
The search for Mr Evans is continuing on Friday, after he went missing on Tuesday.
The 79-year-old was last seen at his Reillys Road home address about 7pm on July 21.
Police and family hold serious concerns for Mr Evans' welfare, as his disappearance is out of character and he has dementia.
Mr Evans was last seen wearing a grey jumper and long grey pants.
Local uniform members have been joined by Police Airwing, Dog Squad, Mounted Branch and Search and Rescue to search Neilborough and surrounds.
Police are being supported by the Country Fire Authority, State Emergency Service, Parks Victoria and the Department of Environment, Land, Water and Planning.
Investigators have released an image of Mr Evans in the hope someone recognises him and can provide information about his whereabouts.
Anyone with information has been urged to contact Bendigo Police Station on 5448 1300.
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