Dr Michael Mosley still missing after 67-year-old columnist vanished on Greek island Symi

A major search operation is continuing for author and TV star Dr Michael Mosley, who has vanished during a walk on a Greek island.

Police fear Dr Mosley, 67, may have ‘slipped, tripped or fallen’ while hiking alone in blistering 36C (97F) heat on Wednesday.

His wife, Dr Clare Bailey, 62, raised the alarm when he failed to return home by 7.30pm and local authorities began tracing his route overnight.

Police filed a missing person report at 10.30am on Thursday and Athens sprang into gear to support the tiny holiday island of Symi.

By midday, each of the emergency services in Greece had been seconded by local authorities to find the world-renowned exponent of the 5:2 diet, who was last seen leaving Saint Nicholas beach towards the town of Pedi, via a rocky path with steep sections.

The coastguard scoured the sea, the fire brigade searched the remote island’s forests and hills, with a drone flying overhead and volunteers also helping with the search.

‘Any and every attempt to track him down has not produced any result,’ Greek police spokesman

Constantina Dimoglidou told the Mail. ‘He may have slipped, tripped, fallen, even been bitten by a snake, remaining injured somewhere.

‘There is just no trace of him. None whatsoever. And that means that for us at least, every potential scenario is open and being investigated.’

Dr Mosley and his wife landed on the 25-square-mile island on Tuesday and were due to stay for a week with a couple who have a house in Symi Town.

The two couples took a boat up the coast on Wednesday morning. They stopped at Saint Nicholas beach where the diet doctor, a father of four, went for a swim in the sea before deciding to walk the 2.2 miles back home at 1.30pm.

He had left his phone at their friends’ home, and when Dr Bailey and the couple returned to the property, they found that Dr Mosley had not returned and his mobile was where he left it.

After the alarm was raised, a woman reported seeing Dr Mosley walking past a bus stop in Pedi, halfway between Saint Nicholas beach and Symi Town

It’s a road that’s been recently widened

There were also claims he was seen talking to someone.

If confirmed, the sighting would indicate he made it past the most perilous coastal segment of the route. But officers could not find any images of the doctor on the limited CCTV in the area.

A resident of the island and friend of the couple Dr Mosley was staying with spoke to BBC Radio 5 Live about the part of the island he was believed to have walked through.

‘It’s a road that sort of heads over the mountainside but it’s been recently widened and there is only one route, so it’s not possible to lose your way,’ she said. ‘It’s not possible to get lost up there.

‘So it is probably a 20-minute walk down the side of the mountain, but it’s not overly rugged or something that would be seen to be too dangerous – it’s something tourists do every day in the summer.’

Ms Dimoglidou said: ‘We’re looking everywhere for him’, adding that Dr Mosley may have become dizzy from the heat. ‘It’s rugged terrain with high spots, so it’s possible that he fell’, she said.

There are several rocky outcrops along the route to Pedi and it was feared Dr Mosley could have fallen into the sea.

Once past the small coastal town of Pedi, the route to his holiday home involves main roads lined with houses. Symi mayor Lefteris Papakalodoukas said the area where the presenter went missing was considered ‘difficult as it is quite rocky’.

‘He came back from the beach, some people saw him but then his tracks were lost,’ he said, adding that Dr Mosley ‘wanted to walk back from the beach, but that’s a distance of about an hour and a half and there are shortcuts he may have taken’.

Mr Papakalodoukas added: ‘The British broadcaster has come for holiday with his wife and is being hosted by a couple of their friends on our island. We know he had gone for a swim... but because he likes hiking and the area, he (decided he) would walk back.

‘Some witnesses said he was seen returning to Pedi and talking to another person. All of these are testimonies that are being investigated at the moment.’

Mr Papakalodoukas told the local paper, Kathimerini, that the high temperatures on the island on Wednesday were ‘unbearable’ and that ‘one could easily faint in such conditions’.

An excessive heat warning was issued by the Greek meteorological service on the day Mr Mosley went missing.

“Nothing can be ruled out”

Police last night said the search was focusing on the Pedi area where the alleged sighting was made by a local woman. A helicopter has been brought in and a special police dog unit will arrive today.

Police confirmed ‘all involved parties have been questioned’. Greek police officials acknowledged that the disappearance of such a high-profile figure posed a huge challenge at the start of the tourist season.

‘He may have slipped and fallen, perhaps because of a heart attack along the way,’ a police source said.

‘Nothing at this stage can be ruled out.’

The Mail understands the police are leading the investigation, which indicates they believe he has gone missing on the land, but the coastguard is assisting.

Presenter Jeremy Vine, who has featured Dr Mosley on his BBC radio 2 programme, wrote yesterday:

‘I’m praying this lovely man is found and thinking of Clare and the whole Mosley family.’

A Foreign Office spokesman said last night: ‘We are supporting the family of a British man who is missing in Greece and are in contact with the local authorities.’