It's been nearly 50 years since an American fighter jet went down off Britain's coast, spawning a conspiracy theory that persists until this day.

The official conclusion was that a tragic accident brought down the plane piloted by US Air Force pilot Captain William Schaffner.

However reports of bizarre sightings in the sky fuelled intrigue and mystery - and speculation that fighter jet XS894 was downed by UFOs.

There were claims of flying transparent spheres and unusual blips on the radar, the Grimsby Telegraph reports.

And the pilot's body was missing when the aircraft was discovered on the seabed weeks later with its canopy closed, only adding to the mystery.

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