The family of a missing man from the Penzance area are urging people to check their outbuildings for him.
David's niece, Claire Newby, has taken to social media to share updates of her missing uncle describing his disappearance as "out of character".
Posting details on Facebook, she says David's car - a silver Nissan Note - was located in Mullion on the Lizard.
She says police search and rescue teams are looking in the area surrounding his car and beyond. Claire says David has dementia and may be lost.
She added this morning, Friday 17 November: "We need out buildings checked in Mullion. So many people don't have social media here."
Police are growing concerned for David's welfare, following his disappearance on the afternoon of Friday 10 November.
He is described as a white male, of slim build with shoulder-length light brown/grey hair. He is 5ft 7in tall, police said.
David was last seen wearing blue trousers, green wellies and a black O’Neill ski coat. He has butterfly tattoos.
If you have seen David, or know of his whereabouts, you are being asked to call Devon and Cornwall Police immediately on 999, quoting log number 443 of 15/11/23.