PHOTO: France has revealed secret images of aliens and their spacecraft

UFOs always generate intense interest, and they generate conspiracy theories about the government’s hidden findings for the public that are too sensitive or disturbing.

Of the 1,600 cases registered since 1954, nearly 25 percent were classified as “D”, meaning good or excellent data and trusted witnesses. Scientists say we are confronted with something we can not explain.

Other countries collect data on UFOs more systematically, especially in the UK and the US where information can be requested under the Freedom of Information Act.