On November 29, 1989, at least 143 witnesses, including 13 on-duty police officers, reported a massive silent triangular craft with white lights at each corner hovering over Eupen, Belgium. The Belgian Gendarmerie formally documented the accounts the same night.

Officers Heinrich Nicoll and Hubert Von Montigny were the first to file reports, describing a flat black platform roughly the size of a football field moving without sound. Their accounts were corroborated by separate patrols across the region and by NATO Glons air defense radar returns in the same area.