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The mystery of the strange blue glow seen moving through the skies over Buckinghamshire on Wednesday night appears to have been solved.

And is seems it was not down to aliens - despite a wave of rumours on social media.

Pictures emerged from across the county of an eerie blue light travelling slowly overhead.

Lots of theories have been put forward, including a UFO, blue alien eyes and light pollution.

The blue light moved across the sky and was spied from Chinnor and Thame to High Wycombe and Gerrards Cross, as well as in Oxfordshire. 

READ MORE HERE: UFO sighting? Strange 'blue glow' spotted moving across the sky over Bucks

However, a video has emerged which appears to show the cause of the blue glow.

This CCTV video, posted on Facebook by Shelley Ifill, captures a train moving at speed at 9.15pm on Wednesday with a blue light shining from the roof towards the sky.

It's not yet known exactly where the video was shot.

Rail companies have been contacted to establish which train was carrying the powerful beam, and why.