The Pentagon says there's evidence the U.S. covered up the existence of UFOs. The Department of Defense released a 63-page report on "unidentified anomalous phenomena" on Friday. It said, "Investigative efforts determined that most sightings were the result of misidentification of ordinary objects and phenomena." The report also said there is "no empirical evidence for claims" that the government and private companies are reverse-engineering extraterrestrial technology.