The files are the largest disclosure of declassified documents released to date online by the National Archives and can be downloaded at no cost for the next month.
The documents include stories, drawings, letters, a House of Lords UFO debate, details about a flying saucer hoax that was thought to be an alien invasion of the U.K. and fascinating facts about how 1978 almost became the "year of the UFO."
"These documents show absolutely beyond a doubt that over many, many years, Ministry of Defense officials, government ministers and defense intelligence staff have treated the UFO issue seriously," Nick Pope told AOL News.
Pope headed up the British government's UFO project, analyzing classified files at the Ministry of Defense from 1991 to 1993.
"The Ministry of Defense's position was: We don't know what these things are, we don't believe they're of any defense significance. But it remained open-minded about the possibilities of extraterrestrial life," Pope said.
One file, designated DEFE 24/2032 (p10-34), is titled "U.N. Discussions on UFOs." It "contains papers dealing with United Nations discussions on UFOs in 1977-1978 generated by the Foreign & Commonwealth Office and the [Ministry of Defense]."
The document reveals how the Ministry of Defense used its influence to stop the country of Grenada from getting the U.N. to form a special agency to conduct UFO research. Grenada continued its campaign "for a full U.N. debate on UFOs, calling on the U.N. General Assembly to make 1978 'the year of the UFO.'"
This reporter is well aware of the 1978 event. I was the person who produced the entire UFO U.N. presentation for Grenada.
Two months after that event, according to the same file, DEFE 24/2032, the House of Lords held a full debate on UFOs in the British Parliament. In that debate, the government spokesman, Lord Strabolgi, said, "There is nothing to convince Her Majesty's Government that there has ever been a single visit by an alien spacecraft.
"As for telling the public the truth about UFOs, the truth is simple. There really are many strange phenomena in the sky, and these are invariably reported by rational people. But there is a wide range of natural explanations to account for such phenomena," Strabolgi stated.
Could "natural explanations" explain all of the accounts in these X-Files?
In one case, from 1967, the threat of an alien invasion was taken seriously by the British military. As highlighted by The Telegraph, police, armed forces and intelligence services were mobilized after several alleged flying saucers were found throughout southern England. It turned out to be a practical joke created by engineering students.
Then there was the case of a family that photographed as many as 30 UFOs on camera near Heathrow Airport in 2003, but radar showed nothing unusual.
The UFO X-Files -- a term often related to the popular science fiction television series that has since come to refer to government cover-ups and documents on paranormal activity -- contain many drawings and photographs of unexplained objects in the skies over Britain, such as a photo of a doughnut-shaped phenomenon snapped by a retired RAF officer.
And another file tells of the crew of an RAF Tornado aircraft, returning to Germany from Britain, when they were startled by a huge UFO while they flew over the North Sea.
The British National Archives contains many other UFO files previously released by the Ministry of Defense from 2008 to 2010. Some of those documents allege that former Prime Minister Winston Churchill was concerned that UFO information might create a panic in the general population.
While the British files are gaining attention all around the world, a dispute is brewing between UFO skeptics and believers in Brazil over the authenticity of an amateur UFO video.
While experts generally agree, in and out of Britain, that most UFO accounts end up having non-alien explanations, approximately 5 percent of sightings worldwide have not been satisfactorily explained. These reports are simply labeled as unidentified.
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