The search for Dr Michael Mosley is now a “race against time” as firefighters probe a cave system known by residents as “the abyss”.
The cave network, which lies off a picturesque beach, is made up of dozens of tunnels that can quickly fill with seawater, according to locals.
Dr Mosley was last seen leaving Saint Nikolas beach at 1.30pm on Wednesday, when he is believed to have been heading off on the coastal path back to nearby Pedi.
“It’s like a deep system of tunnels, but it is full of water and can spread for kilometers. There is a reason they call it ‘The Abyss’. There is something very strange going on,” a waiter told The Daily Telegraph.
Meanwhile, Dr Mosley’s wife said she would “not lose hope” over the search for her husband and thanked Greek authorities for their “tireless” efforts.
“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 said.
