The wife of missing British doctor and television presenter, Michael Mosely, has spoken out of the family's hopes he will be found alive on the Greek Island of Symi.
Dr Clare Bailey Mosley released a statement saying the days since her husband was last seen have been "the longest and most unbearable" but the family "will not lose hope".
"It has been three days since Michael left the beach to go for a walk," she said in the statement.
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"The longest and most unbearable days for myself and my children.
"The search is ongoing and our family are so incredibly grateful to the people of Symi, the Greek authorities and the British Consulate who are working tirelessly to help find Michael.
"We will not lose hope."
Dr Clare Bailey Mosley's statement comes as their four children travelled to Symi to join the search for their father.
CCTV footage emerged this morning of the last sighting of Mosley before he went missing on the small eastern Aegean island on Wednesday afternoon.
"We are very shocked and perplexed by what has happened to him," Mosley's brother Arthur told UK newspaper The Telegraph.
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"We know as much as what the police and the media has reported, but we are closely following the situation, and hope that there's a good outcome," he said.
"Unfortunately, when you get to my age or his age, accidents like this can happen."
Greek police are undertaking a major search for Mosley who went missing after going for a walk.
The CCTV footage shows the doctor in the nearby village of Pedi just 20 minutes after he started his stroll from Agios Nikolaos beach in Symi.
He can be seen standing in the village's main street holding an umbrella.
Police said on Friday that the coast guard, police and fire department were involved in the search, with a helicopter, drones and a police sniffer dog deployed.
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The search was called off at 8pm (local time) and will resume again on Saturday morning.
They have found no trace of the 67-year-old who had been vacationing on the island.
The search was focusing on the area between Agios Nikolaos, the coastal area from where Mosely apparently set off on his walk, and the island's main town of Symi. Authorities had also looked into whether he might have left the island altogether, but found no indication that anyone had travelled under his name.
Britain's Foreign Office said it was in contact with Greek authorities over the search.
Mosley is well-known in Britain for his regular appearances on television and radio and for his column in the Daily Mail newspaper.
He is known outside the UK for his 2013 book The Fast Diet, which he co-authored with journalist Mimi Spencer. The "5:2 diet" set out how people can lose weight fast by minimising their calorie intake for two days in a week while eating healthily on the other five.
He has subsequently introduced the Fast 800 diet, a rapid weight loss program, and has made a number of films about diet and exercise.
Mosley has often pushed his body to extreme lengths to see the effects of his diets and also lived with tapeworms in his guts for six weeks for the BBC documentary Infested! Living With Parasites.
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Worried friends and colleagues expressed their shock over Mosley's disappearance.
"This shocking news focusses our minds on Michael's wife Clare and their sons," said Roy Taylor, a professor of medicine and metabolism at Newcastle University who co-authored The 8-Week Blood Sugar Diet with Mosley.
"Our thoughts are with them in this terrible time of uncertainty, hoping that he will be found safely."
In 2002, Mosley was nominated for an Emmy for his executive producer role on the BBC science documentary The Human Face, which was presented by Monty Python star John Cleese and which featured a raft of famous faces including Elizabeth Hurley, Pierce Brosnan and David Attenborough.
Mosley has four children with his wife Clare Bailey Mosley, who is also a doctor, author and health columnist.
