It has all the elements of a conspiracy theorist’s dream: previously classified documents with sections still blacked out by censors, an alleged alien abduction in Ilkley, and a mysterious and unexpected evening visit by suited men.

The tale of a man’s brush with extraterrestrials and the Men In Black is just one to emerge from a set of UFO-related documents released today by the Ministry of Defence.

More than 4,500 pages of material has been published under the Freedom of Information Act today, including letters and reports on UFO sightings and encounters across the country – and the Telegraph & Argus even gets a mention.

The massive collection of unexplained incidents is composed mainly of reports by civilians which were impossible to verify or disprove, and cover reported sightings between 1986 and 1992.

Dr David Clarke, a UFO expert and journalism lecturer at Sheffield Hallam University, described such insights as invaluable: “These files contain a rich mixture – everything from close encounters between aircraft and UFOs, to stories from members of the public who believed they were in contact with extra-terrestrials.

“It’s great news that the National Archives continues to make these accessible on a dedicated website that contains such a wealth of useful information on the topic.

“Making the material available to all those who have an interest in this subject means that everyone, expert or amateur, can make an informed decision on the mystery of UFOs.”

From this treasure-trove of paranoia and phenomena, the travails of the anonymous Ilkley man certainly catch the eye.

His claim to have been abducted by aliens was being investigated by the delightfully-named Manchester UFO Research Association in 1988.

But his run-of-the-mill encounter of the fourth kind took a really bizarre twist when, out of the blue, he was visited by two men who “wore smart business suits, were in their 40s and produced identity cards claiming they represented the MoD”. This prompted the Manchester UFO Research Association to write to the MoD and ask if these two mysterious callers were indeed on Government business.

The letter also asks whether the MoD ever conducts such investigations with plain-clothes officers and, if so, how on earth it could have known about the abduction claim, as no Government department had been informed of it.

Sadly, no reply was available in the documents released, and we can only hope the Ilkley abductee has been left in relative peace by alien abducters and Agents K and J.

The T&A makes a fleeting appearance in the archive with a letter from a man who, while walking to his car one evening, had the eerie feeling that what he was seeing was no aircraft but something “peculiar”. Although his tale of seeing a UFO begins with the ominous words “on the night of the 12th of September 1988 I was leaving the Prince of Orange Inn situated on Carr House Road, Shelf”, his bona fides seem impressive.

He was a duty controller at Manchester Airport – not a role in which one expects to find someone of a dreamy disposition – and stressed that he had not allowed a single drop of alcohol past his lips that night.

He said: “My health that night was perfect as it generally is and I am not prone to bouts of hallucination nor do I consider myself to be in possession of an over-active imagination... I have considerable experience as an amateur astronomer and therefore would not be prone to misidentification of aircraft unless they were viewed under very strange conditions.”

What’s more, he was not the only person to have seen “it” – whatever it may have been. A report in the T&A on September 17, 1988, had three other witnesses corroborating the account.

Another account from 1988 comes from an off-duty policeman. On February 18 at 7.30pm, he was travelling in by car along Toller Road towards Bingley with his wife and child when they saw moving stars and pulled over to take a closer look.

The sub-divisional officer, based at Bradford Central, wrote: “On first seeing the object could have been an aeroplane even though we could not see any coloured lights but when the object changed direction suddenly and accelerated we were sure it was not.”

Another report in the files tells of a ten-year-old keen astronomer who called 999 to report “two