An airman has witnessed a ' UFO ' while he was guarding nuclear weapons at a US Air Force base - adding that he's seen 'shadow people' at similar installations.

Former USAF nuclear weapons technician Adrian Reister said that between 2003 and 2007 he was stationed at Whiteman Air Force Base, Missouri, where he would guard, maintain, and move nuclear weapons.

He said that while performing his duties, he saw a glowing 'orb' hovering above a nearby treeline before flying off, as the Daily Star reports.

Adrian, 37, said that it couldn't have been one of their planes as he knew them all extensively, and he added that while he was training at a similar station he came face-to-face with a terrifying 6ft 'shadow person'.

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