The wife of missing walker Finn Creaney has appealed to anyone who may have seen her husband to get in touch with police.
Mr Creaney’s partner said it is now seven days since his family last saw him.
The 32-year-old, from the Tain area, was dropped off on the afternoon of Friday 25 March on the B873 at Loch Naver, with plans to walk south around the loch and head to Golspie.
Police Scotland said officers are continuing to search the area between Altnaharra and Golspie in Sutherland, with the operation to find Mr Creaney involving its air support unit as well as a number of partner agencies, including mountain rescue teams and the Coastguard.
Mr Creaney’s wife Lucy said: “I would like to thank family, friends and the local community for all their help, concern and support over the last few days. It is a really worrying time for me and our four-year-old daughter, Luna.
“I am really concerned for Finn as it has now been seven days since we last saw him.
“I want to appeal to anyone who may have seen Finn since last Friday to call the police and ask anyone walking in the area and hills between Altnaharra and Golspie that they keep an eye out for Finn and keep him in their thoughts.”
Mr Creaney is described as 5ft 11ins (1.8m) tall, slim build, with light complexion and freckles on his arms and nose. He has long brown hair down to his lower back and a full brown beard.
He was last seen wearing a black t-shirt, a knee-length brown leather jacket, dark coloured trousers, brown waterproof boots and was carrying a green rucksack.
Inspector Alasdair Goskirk said: “Our concerns for Finn’s safety and welfare continues to grow. Extensive searches and enquiries have been carried out in an effort to trace Finn.
“I know our concerns are shared by locals and we are grateful for the assistance we have received so far.
“Anyone who may have seen Finn or has any information which could assist should call 101, quoting reference 0912 of 28 March.”