Officers are "urgently" trying to trace a man from Leeds who has been missing since the weekend.
John Preston, from Armley, was last seen on Sunday and police have since been searching for the 46-year-old.
They believe he may have links with the Doncaster area.
Detective Inspector James Entwistle, of Leeds District CID, said: "John was last seen on Sunday afternoon and we are urgently seeking to make contact with him as we have concerns for his welfare.
"John, or anyone who has information about John's whereabouts, is asked to contact Leeds District CID on 101 referencing log 405 of June 13"