Long Bennington man Derek Foster, 83, has been missing for two weeks and there has been no potential sighting of him since December 28.
Police and friends who are searching for him say it is a complete mystery. Mr Foster, full name Jack Derek Foster, went missing on December 23 and was last seen at Grantham bus station at about 2.30pm. He was seen in the bay where buses for Bottesford depart but it is not known if he got on a bus. Searches in Grantham, Long Bennington and Bottesford have been unsuccessful.
Police say there were 10 potential sightings of Mr Foster up until December 28, but none since. The last potential sighting was on the A607 between Fulbeck and Leadenham when an elderly man was seen walking along the road in the direction of Grantham.
A police spokesman said: “The search is still ongoing. We have not given up hope. With the weather being so cold it is obviously very worrying. It is a complete mystery”
Friends of Mr Foster have set up a Facebook page at Facebook.com/Searchforderekfoster
The latest search took place along Barrowby Gate stream on Sunday. Mr Foster regularly visited a friend at St Edmunds Care home and friends believe he may have tried to make his way there. They are asking people in the area to check their sheds and outbuildings for any sign of Mr Foster.
If anybody has any information on Mr Foster they should call police on 101.