Sighting in Paris, May 17, 2015

Shortly before one in the morning, during the night from Saturday to Sunday, a witness who was closing a window was surprised to see five or six coloured balls of light crossing a clear sky. They moved without making any sound and seemed to mark out the outline of a dark craft. The witness described it as a "grey and metallic" craft carrying six large coloured balls of light. The sighting lasted only a very short time, and the lights went out suddenly.

The investigation considered that the witness may have been fooled by a shape illusion, in which case only the balls of light would be real and not the grey craft. Balls of light crossing the sky in a straight line on a weekend night suggest Thai lanterns, probably released nearby after a private party. Their disappearance could be explained by them burning out or passing behind a building. Because the sighting was so brief and the witness did not give any directions of movement, it was not possible to check whether the motion fitted with the wind. A drone seemed unlikely: flying one at night in a city is difficult and risky, and drones tend to follow non-linear paths. The GEIPAN received no other testimony that could match this phenomenon. The case was classified C because of the lack of precise information and of corroboration.