William, 90, was last seen at Greggs, in the Kirkgate, around 4pm. Due to falling temperatures, police increased the number of officers in the search that has centred around Leith and his home in Chesser.
Police confirmed the use of a helicopter in the search after residents took to social media to report seeing it circling around Leith and Trinity on Sunday.
A dog unit has been dispatched in the search for William, who lives with dementia and various other medical conditions, for which he requires medication.
The coastguard has been assisting the police in searches of the Leith shoreline.
Police Inspector Caroline Flynn said: “We are still extremely concerned for William’s welfare who has now not been seen since Tuesday.”
“I have a team of dedicated officers carrying out inquiries. Searches are focussing on the Leith area where he was last seen. Local officers are being supported by specialist search teams, the police helicopter and dog unit. I would encourage people to check outbuildings, sheds and garages where William may have sought refuge from the cold weather.”
William’s granddaughter Charlotte Gibson issued a plea for people to continue searching outbuildings and gardens in the search for her “caring and thoughtful” granddad.
She said: “It’s been hard for the family. We have a small but very close family and he’s very much at the centre of it. There’s five grandchildren who have Christmas cards for him and starting to wonder where’s grandpa? “I just really want to find him and know where he is now.”
Anyone with information is asked to contact Police Scotland on 101 quoting incident 3338 of 11th December.
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