SIOUX FALLS, S.D. (KELO) -- South Dakota has had at least 433 reported sightings of unidentified flying objects (UFOs) since 1897, according to the National UFO Reporting Center (NUFORC) website. The reporting sighting in 1897 was an "object descends and follows locomotive." The website credits the book "SDUFO: A Case History" (2004) by Greg Nedved [...] ...read more read less