GETTY Three top secret files on UFOs promised for release have been held back.

UFO and alien truth seekers have been eagerly awaiting the release of 18 MoD reports into UFO cases, after a series of hold ups in getting them made public via the National Archives. But, there are claims the truth still isn't out there after three of them were still not released, and officials appeared to make it very difficult for anyone to view the 15 others. Instead of being placed online as many National Archives documents now are, the papers can only be seen by making an appointment with the Government archive service in London. Or copies can be ordered for a fee online with several days wait before they they arrive. Nick Pope, who worked in the department of the MoD which investigated UFOs until 2009 and now speaks at alien-related conferences across the globe, said there would be claims they had been "snuck out". He said: "It seems that The National Archives has released 15 of the remaining 18 Ministry of Defence UFO files, marking the final stages of what's been a nine-year long project to declassify and release the MoD's entire archive of UFO files.

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"Unlike all such previous releases of UFO files, I wasn't pre-briefed on the release date. The release of these final files has been extensively delayed and at one stage they were sent from the MoD to the National Archives, but then sent back to the MoD. "Embarrassment about this delay may explain why - unlike releases of previous batches of MoD UFO files - there hasn't been a proactive media release. "Accordingly, I suspect the UFO and conspiracy theory community will say that these files have been "snuck out' "I think one has to pay for access, unlike previous batches, which were free for a month." But, he said he did not believe there was a smoking gun of evidence for alien life in the files as had been hoped. Those hoping the files could solve the mystery of the December 1980 Rendlesham UFO case may also be disappointed, he said. The UK alien sighting happened when three US officers based at RAF Bentwaters, near Woodbridge, Suffolk, claimed a "triangular shaped craft" landed in neighbouring woods in the early hours of December 26.

I believe there are some documents on the Rendlesham Forest incident, though I'm pretty sure they're duplicates of material that's been released previously. Nick Pope

The case was later investigated by the UK Ministry of Defence (MoD), but it concluded there was no evidence of alien visitations or any national security risk, and the sightings were most likely the result of beams of light from a nearby coastal lighthouse. Truth seekers believe there is more to it and the files might solve the mystery. Mr Pope said: "I believe there are some documents on the Rendlesham Forest incident, though I'm pretty sure they're duplicates of material that's been released previously. "The release of these real-life X-Files shows that the UFO mystery lives on and that there's still huge interest in this fascinating topic. "These files will give people a revealing insight into this bizarre and intriguing aspect of Ministry of Defence business. "I think these files perfectly capture the wonder and fascination of the UFO mystery and show how MoD officials - myself included - struggled to make sense of one of the great mysteries of the modern era.

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