The TV doctor has not been seen since going for a walk alone yesterday afternoon.

An appeal for his whereabouts was shared in a local Facebook group after he went off for a walk on his own at 1:30pm yesterday afternoon and hasn’t yet returned to his family.

Police have now intensified the search after no progress was made overnight.

Twenty-five police officers and firefighters have been using drones and a specialist dog unit to scour the island, which is part of the Dodecanese island chain and is about 25 miles north of Rhodes.

The temperature is set to rise to 35C today, increasing concerns about Mosley’s wellbeing. Local officials described the temperature on the island as ‘unbearable’ yesterday.

Yesterday’s appeal on social media read: “A search and rescue team is coming from Athens with drones and other more sophisticated equipment to extend the search.

“They are expected to arrive by about 1 p.m.”

The post, which included a picture of the well-known medic, added: “Have you seen this man? He set off to walk back from St Nick’s at about 13.30 and failed to make it home. His friends are concerned as it is 6 hours since they last saw him.

“His name is Dr Mike Mosley and he is a familiar face for many British people.”

Dr Mosley also hosts the Just One Thing health podcast for the BBC and is credited with the rising popularity of the 5:2 diet for losing weight.

The rescue operation is said to be focusing on the Pedi area of the island after a woman reported seeing him there on Wednesday.

Mayor of Symi Eleftherios Papakalodoukas said firefighters had told him they believed it was ‘impossible’ Mosley was still there.

He told the BBC: ‘It is a very small, controlled area, full of people. So, if something happened to him there, we would have found him by now.’

Friends and colleagues of the TV doctor have been expressing their concern and hopes for his safe return.

Reacting to the “shocking news”, his fellow Trust Me, I’m A Doctor co-star Dr Saleyha Ahsan said she was “praying he is found safe” and she feels “sick with worry”.

On Thursday’s edition of The One Show, presenter Alex Jones opened the programme by expressing concern that “our friend” had gone missing.

“Our thoughts are very much with his wife Clare and the rest of his family at this worrying time. We hope for more positive news,” she added.

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