Authorities believe it's 'impossible' This Morning doctor Michael Mosley is still where he went missing

Authorities in Greece have given a concerning update on This Morning doctor Michael Mosley, who went missing after going for a walk on the island of Symi.

The 67-year-old went missing after going for a walk along St Nicholas Beach at 1.30pm on Wednesday 5 June.

His wife, Dr Clare Bailey, raised the alarm after he failed to return by 7.30pm, with police in Athens confirming yesterday they were ‘actively pursuing the case’.

Speaking earlier this week, Senior Police Spokesman Constantina Dimoglidou said: "He was at the beach of Ag. Nikolas with another couple when he decided to go back to his home in the area of Pedi of Symi.

"It was around 1.30pm and he forgot his phone at the beach. Any and every attempt to track him down has not produced any result.

"We have now asked the fire brigade to assist in the operation in the case that he may have slipped, tripped, fallen, even 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."

A picture that has been used in an appeal to anyone who might have seen him (Facebook)

After Greek police were informed of the 'disappearance of the 67-year-old British national on the island' on Wednesday, they requested assistance from the Greek fire service, with six firefighters, a vehicle and a drone team arriving from Rhodes at about 2pm the following day.

The mayor's office said local people from Symi, a helicopter from Rhodes and police drafted in from outside the island, are searching the Pedi area and surroundings this morning.

However, Eleftherios Papakalodoukas, Mayor of Symi, said firefighters had told him they believed it was ‘impossible’ that 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.”

A friend of the person Mosley was staying with in Greece also said she was struggling to understand how anyone could get lost on that particular part of the island.

Speaking to BBC Radio 5 Live’s Drive programme, she explained: “It’s a road that sort of heads over the mountain side but it’s been recently widened and there is only one route, so it’s not possible to lose your way.

“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 that tourists do every day in the summer.

“I’m having trouble understanding how you could get lost.”

The search for Mosley continues (PA)

Representatives for Mosley said the search was ongoing, telling the Mirror that they are 'very worried about him'.

A spokesperson for 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."

As well as appearing regularly on ITV's This Morning and BBC's The One Show, Mosley is also known for presenting BBC Radio 4's Just One Thing.

The intermittent fasting advocate has published several books including The Fast Diet and The Fast 800.

He has also written a book on using diet to improve sleep called Fast Asleep.