Police have begun to search lakes in part of Lincolnshire following the disappearance of a GP.
Dr James Layfield, from Friskney, who works at the Beacon Medical Practice in Skegness, was last seen by a neighbour on Saturday evening.
He was on foot, wearing light clothing and carrying a black rucksack.
Officers said they were very concerned about his welfare and were searching lakes in the Friskney area on Wednesday.
A police spokesperson said his disappearance was "out of character" and urged anyone with information to come forward.