Relatives of the British explorer Sir Ranulph Fiennes have said it is "very painful" he appears to have been hidden away from them.
Speaking to BBC Newsnight, his former sister-in-law told the BBC that she did not know where he was, and nobody had been able to see him.
It has been alleged that Sir Ranulph, 82, has been admitted to a number of care homes under assumed names, after a family rift involving his second wife, Louise Millington-Cotes.
Louise Millington-Cotes did not immediately respond to the allegations, or the BBC's request for comment.
Cheshire Police have said they are aware of the concerns regarding Sir Ranulph, and are satisfied he is living in an appropriate setting with suitable care.
They said there were "no immediate safeguarding concerns".
Sir Ranulph has not been seen in public for nearly two years, just months after opening up about a diagnosis of Parkinson's disease.
He was the first person to visit both north and south poles by surface means in the early 1980s and has been described by The Guinness Book of Records as "the world's greatest living explorer".
Spending his childhood between the UK and South Africa, he joined the British Army after leaving school, going on to serve in the SAS.
Sir Ranulph's stepson, Alex Millington-Cotes, told BBC Newsnight he wanted to see the power of attorney "removed from my own mother" and placed in the hands of people who "have fully his best interests in mind".
"He's not an isolated type of person, and so to see him isolated now is very painful," he said.
Questions about Sir Ranulph's whereabouts grew in prominence after a report in the Telegraph earlier this month, external in which "members of his inner circle" raised concerns about his whereabouts.
Last week, he launched a crowdfunding campaign for legal fees to "locate and safeguard" the explorer.
He wrote that the fundraiser had been created as "a result of our concern and desperation" after trying "multiple avenues" to locate his stepfather.
Arabella Pepper, the younger sister of Sir Ranulph's late first wife Ginny, told BBC Newsnight that she had not been able to see her former brother-in-law for over a year.
"All his friends and family want to see him and take him Toblerones and cheer him up, but we don't know where is, and he's not available, he's not accessible - that's what worries us," she said.
She alleges that she was only able to see him in July 2025 after she admitted herself to a care home where she had been told he was staying.
"The first thing I said to him, apart from the usual greetings, was that everybody was worried about him, was looking for him, was longing to see him," Pepper told the BBC.
"The relief on his face was very obvious, and he said, send a message to everybody, send them my love, tell them I love them and tell them I'm longing to see them."
Starting in 1967, Sir Ranulph has been the leader of almost 20 major expeditions, according to the Explorers Club.
His expedition to both the north and south poles came during the Transglobe Expedition, in which he led the first team to circumnavigate the globe from north to south.
Sir Ranulph has also enjoyed a career as a prolific travel writer, as well as authoring fiction, non-fiction and biographies.
