"We will not lose hope," the wife of missing TV and radio presenter Michael Mosley has said, as efforts to find him continue on the Greek island of Symi.
The 67-year-old vanished after setting off on a walk on Wednesday.
His wife Dr Clare Bailey Mosley said in a statement that the days since he went missing had been "the longest and most unbearable".
Teams of police, firefighters and volunteers are now into a fifth day of searching for Dr Mosley, known for his TV programmes and BBC Radio 4's Just One Thing podcast.
Emergency crews in the area called off the search on Saturday evening as night fell as the search area is too dangerous to explore in the dark.
Efforts to trace Dr Mosley are due to resume on Sunday morning.
In her statement, Dr Bailey Mosley said: "It has been three days since Michael left the beach to go for a walk. The longest and most unbearable days for myself and my children.
"The search is ongoing and our family are so incredibly grateful to the people of Symi, the Greek authorities and the British Consulate who are working tirelessly to help find Michael.
"We will not lose hope."
Dr Bailey Mosley has been searching the island assisted by friends. The couple's four children have also arrived on Symi to help with the search.