Uruguay (Montivideo), January 1958January 1958

In January 1958, a single observer in Montevideo, Uruguay reported watching an unusual object descend to a low altitude and emit sparks. The observer described the object as circular with a glowing fluorescence around its edges. The sighting lasted about thirty minutes. According to the witness, the object was roughly the size of a tennis ball, yellowish in color, and descended vertically at high speed before slowing down and emitting sparks from the areas around its circular glow. The object then climbed away and disappeared from view in seconds.

The Uruguayan Air Force intelligence center that investigated the case noted that most details in the report matched typical "flying saucer" characteristics. However, they flagged one detail as questionable: the observer's claim of seeing sparks coming from the edges of the glowing fluorescence. The investigators emphasized that because only one person witnessed the event, the account had to be treated with caution. They also mentioned a previous 1955 sighting in another Uruguayan location where a photograph of a similar object with the same glowing ring feature was obtained, though the authenticity of that photo had been disputed by many.

The file does not list a definitive conclusion about what the object was. Without photographs or corroborating witnesses, the investigators could not reach a firm assessment of the sighting.

The full case file is reproduced below as held by the National Archives, comprising 7 pages.