Police believe a man who went missing from his Falkirk home may have travelled to Fife.
Officers believe David Paterson could now be in the St Andrews and East Neuk area.
A full search involving a helicopter and police dogs was mounted on Monday evening and continued throughout the night.
The 52-year-old is described as white and 5ft 3ins in height with dark grey, short, full head of hair that is thinning at the back. He has blue eyes, long eyelashes, big eyebrows and has a dimple on his chin.
He has grey stubble and has not shaven for several days and has broad shoulders and a slim to medium frame and when last seen was wearing a blue fleece, dark denim jeans and lace up light leather tan shoes.
David may be wearing a gold wedding band and a fine silver chain with big links
He may be carrying a dark red rucksack with blue straps.
Inspector Grant Sangster, who is in charge of the search, said: “David’s family are very concerned for his wellbeing and we are doing everything we can to find him, however the assistance of the public is vital in finding him and returning him to his family.
“We are deploying all the resources at our disposal and I would urge everyone to check their gardens, sheds, garages, outbuildings and anywhere else he may be seeking shelter.