David Charles Grusch, an Air Force veteran and former member of the National Geospatial Intelligence Agency, also said the US and other nations are engaged in a top-secret arms race.
The first public meeting of a NASA panel studying what the government calls "unidentified aerial phenomena," commonly known as UFOs, kicked off on Wednesday to discuss its findings since it formed last year.
NASA Kicks Off Study on Unidentified Aerial Phenomena sci.news - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from sci.news Daily Mail and Mail on Sunday newspapers.