The Ministry of Defence went to extraordinary lengths to cover up its true involvement in investigating UFOs, according to secret documents revealed under the Freedom of Information Act. The files show that officials attempted to expunge information from documents released to the Public Records Office under the "30-year rule" that would have revealed the extent of the MoD's interest in UFO sightings. In particular, the ministry wanted to cover up the operation of a secret unit dedicated to UFO investigations within the Defence Intelligence Staff. UFO conspiracy theorists have likened the unit, called DI55, to a sort of "Men in...