CCTV from across Pitlochry is being reviewed in a bid to find a pensioner who has been missing from his home for three days.
William Elder was last seen at his home in James Court sheltered housing complex, where he has lived for at least two years, at around 10.45am on Tuesday.
The search stepped up on Thursday with a sniffer dog being brought in to assist officers.
The dog led the search from James Place down Tom-Na-Moan Road and Toberargaren Road before heading for the main shopping precinct on Atholl Road.
Sergeant Caroline MacNaughton, who is coordinating the search, said the dog was able to pick up a trail in the town centre in areas where they had previous sightings of Mr Elder.
She appealed for anyone who saw Mr Elder in the town centre to contact police.
Police have also been looking at CCTV footage in a bid to establish Mr Elder’s movements.
Sergeant MacNaughton is also asking anyone with private CCTV which may have captured Mr Elder on lanes or private property to come forward.
Staff at the Co-Op store on West Moulin Road, where he went every day to buy a paper, said police had taken away tapes containing security footage from Tuesday morning.
Stuart Fraser, the store manager, said his employees were concerned for the 81-year-old’s wellbeing.
“We are all concerned for him there hasn’t been a member of staff who hasn’t mentioned his disappearance,” he said.
“Pitlochry is a small town and I think this affects everyone in one way or another. Most of my staff are very local and their families are very local.
“We don’t know for sure (that he visited the shop on Tuesday) but we have been looking at our footage. Police have taken our CCTV to search it.”
Nicola Coleman, a supervisor at Hettie’s Catering in Pitlochry, and who lives near to Mr Elder’s home, said Mr Elder was well-known in the town.
She said: “I am concerned. It’s bad when anyone goes missing.
“It’s not nice to surmise but you hope he is somewhere and doesn’t realise the concern he’s causing.”
Residents at James Court sheltered housing, which is run by Perth and Kinross Council, are also worried about their neighbour.
A council spokesman said: “Staff and residents at James Court are very concerned about Mr Elder’s welfare.
“Council staff are assisting the police in any way they can during the search. We all hope for Mr Elder’s safe return.”
Mr Elder has a distinctive limp and uses a walking stick and is described as 5ft, slim with greying hair.
When last seen he was wearing a green wax jacket, black loose-fitting trousers and brown boots.