Stewart Liddell, 69, was reported missing yesterday evening, Tuesday, March 31, after he was last seen leaving his home in Rowlands Gill for a walk at about 11am.
Police have been searching for Stewart overnight and a large-scale operation to locate him is ongoing on Wednesday, April 1.
Superintendent Karl Wilson said: “We have a significant number of resources out looking for Stewart and that will continue throughout the day.
“We are very concerned for his welfare, particularly considering he has spent the night away from his home and his family.
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“If anyone has seen a man matching Stewart’s description in the area of Derwent Walk, perhaps on your once daily exercise, then we would urge you to get in touch.
“Please don’t leave your homes to try and join the search efforts as we need people to continue to follow the stay at home guidance and there are a significant number of police resources in the area.
“We would ask you instead help us by sharing our appeal and contacting us if you do believe you have seen Stewart since yesterday morning.”
Stewart is described as 5ft 2in tall, of thin build, with grey hair and no longer has the moustache as seen in the photo.
He is believed to be wearing a dark blue fleece, white jumper and carrying a green canvas bag.
If you have seen Stewart then we would ask you contact police on 101 quoting incident number 757 31/03/20