Major search for missing Bonar Bridge man Peter Ripley
Members of the public have volunteered to join search and rescue teams in an effort to find a man missing from his home in Sutherland.
Peter Ripley, 60, was last seen in the Swordale Road area of Bonar Bridge at about 21:00 on Sunday.
Police said they were concerned for Mr Ripley because he had gone missing without his daily medication.
Coastguard helicopters, police, two mountain rescue teams and search dogs have been trying to trace Mr Ripley.
He is described as being 5ft 8in in height, of medium build with a bald head and a greying moustache. When he was last seen he was wearing a black Puffa-style jacket, dark jeans, dark boots and was carrying a rucksack.
Searches of Bonar Bridge and the surrounding area have been carried out since Sunday night.
On Monday, a search involved coastguard helicopters, police and members of Assynt and Dundonnell mountain rescue teams.
The effort resumed earlier on Tuesday and involves search dog teams from Search and Rescue Dog Association Scotland and Police Scotland.
Insp Jamie Wilson, of Police Scotland, said: "As we reach day three of the search we are extremely concerned for Mr Ripley's welfare.
"Extensive searching has been carried out to date and will continue with assistance from partner agency and the local community, for which we are very grateful indeed."
He added: "We would reiterate our appeal for local residents to check outbuildings and gardens and be mindful of search activity, reporting anything they feel may assist."