Four technicians - professionals specializing in electricity, electronics, and fluid control - were working there in April, 2013. They witnessed a disc-shaped object which approached slowly and was present for more than an hour, moving around in different positions and hovering at about 2000 feet. One technician took pictures with his Kenox Samsung S860 camera. The strange object made no sound, and eventually moved away towards the East.
The witnesses decided not to tell anybody because of the negative associations they had with UFO sightings, and therefore had every intention of always keeping the sighting private. But some months later, the photographer casually showed the pictures to the chief engineer at the mine, who asked for copies. The engineer sent the images to the CEFAA and provided the agency with information reported to him by the witnesses. He too has requested anonymity.
The report states that the witnesses described the phenomenon as "a flattened disc, of brilliant color, with a diameter of 5 to 10 meters [16 to 32 feet]. It performed ascending, descending and horizontal movements in short lengths, about 600 meters above the ground." The witnesses had the impression that the object was under intelligent control.
The study concludes that "It is an object or phenomenon of great interest, and it can be qualified as a UFO."