New image of Michael Mosley shows last sighting of TV doctor before he went missing

In a shocking twist, CCTV images show much-loved TV doctor Michael Mosley did make it across a coastal path and into a nearby town before vanishing on a Greek island.

Dr Mosley is seen on surveillance footage on the main road of Pedi on the island of Symi at 13.50pm on Wednesday afternoon, around 20 minutes after he is thought to have hiked a coastal route, the Mirror reported exclusively. Up until now, many had thought he may have fainted or fallen off a cliff during the walk.

The CCTV was shared by local site MEGA after being recovered by cops who have been "combing" the island of Symi, where the presenter was holidaying with his wife Dr Clare Bailey.

READ MORE: Blakelaw killer facing life sentence after confessing to murder of Newcastle man Bradley Tams Keep up to date with all the latest breaking news and top stories from the North East with our free newsletter

And a second image, shared exclusively with The Mirror, was captured on surveillance cameras outside the Blue Corner Cafe on Pedi Beach. It shows Dr Mosley shielding himself from the sun with an umbrella as he passes by.

This comes as worried friends - including a Newcastle-based professor who worked with Dr Mosley on a life-changing book - expressed their fears for his welfare. Newcastle University's Prof Roy Taylor said the shocking news "focusses our minds".

Greek police say they're engaged in a major search and rescue operation on Symi, a small eastern Aegean island. But despite their best efforts, they have still not located Dr Mosley.

Police said Friday that the coast guard, police and fire department were involved in the search, with a helicopter, drones and a police sniffer dog deployed. 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 U.K. 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 minimizing 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."

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.