The search continued on Friday for Michael Mosley, a British broadcaster and healthy living advocate, who went missing on the Greek island of Symi.

Mosley disappeared after embarking on a coastal walk alone in scorching heat.

Mosley, a well-known doctor famous for promoting fasting diets, was last seen at 1:30 p.m. (1030 GMT) on Wednesday. He had set out for a short walk along a rocky path between Agios Nikolaos beach and the village of Pedi, according to police.

Police, the fire brigade, coast guard, and volunteers are conducting a land and sea search for Mosley, employing a helicopter, drones, and a rescue dog, as temperatures soared to 40 degrees Celsius (104 Fahrenheit).

Mosley did not have his mobile phone with him, complicating efforts to locate him.

"So far, we don't have evidence of what may have happened, whether it is an accident ... or something else," said a senior police official who wished to remain anonymous.

Police are investigating reports that Mosley had spoken to locals midway through his walk.

Symi Mayor Lefteris Papakalodoukas noted that it is a 10-minute walk from the beach to Pedi and another 40 minutes to reach a main road.

"It is very strange," Papakalodoukas told reporters. "You can't disappear, you can't get lost."

Symi is a sparsely populated, rocky island in the eastern Aegean, approximately 10 miles long with about 2,500 residents.

Mosley, 67, is well-known in Britain for programs such as the BBC series "Trust Me, I'm a Doctor." He has also appeared on the BBC's "The One Show" and ITV's "This Morning." He popularized the 5:2 diet, which promotes intermittent fasting.

There has been an outpouring of concern from colleagues and friends on social media for Mosley and his family. The story was featured on the front page of the Daily Mail newspaper, where Mosley is a columnist. Photo by HEALTHISTA TV, Wikimedia commons.