Dr Michael Mosley has gone missing on a Greek island.
The 67-year-old's agent has confirmed his disappearance to the Press Association.
He is known for appearing on television programmes like This Morning and The One Show. He also hosts the Just One Thing health podcast for the BBC.
An appeal has been shared in a local Facebook group after he went missing on the island of Symi on Wednesday.
The appeal 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 1pm."
The post, which included a picture of the 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."
It is reported his wife raised the alarm.
In a statement, the Foreign Office said:
"We are supporting the family of a British man who is missing in Greece and are in contact with the local authorities."
One user on a local forum in Symi said Dr Mosley "left his phone at his accommodation".
"These days it should be pretty difficult to get lost on Symi as so many of the paths have been surfaced and there is a lot more activity even in the most remote areas," they added.
Symi is part of the Dodecanese island group and is close to Rhodes, which can be reached within an hour and 10 minutes on a ferry.
Dr Mosley was one of the presenters of the series Trust Me, I'm A Doctor on the BBC.
He is also credited for the rising popularity of the 5:2 diet for losing weight, which involves fasting for two days per week.
More recently, he presented two series for Channel 4, Secrets Of Your Big Shop and Who Made Britain Fat?
His programmes have won an RTS and Emmy award and he has previously been named "medical journalist of the year" by the British Medical Association.
(c) Sky News 2024: Dr Michael Mosley: TV doctor goes missing on Greek island Symi
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