Karl Wolfe spoke out more than 30 years after he left his position at Langley Field, Virginia.

Mr Wolfe worked for the US Air Force Director of Intelligence at the Headquarters Tactical Air Command, Technical Group, in Langley Field, Virginia, which was the centre for data and pictures from the NASA Lunar Orbiter Project.

He said he was one of only two technicians at Langley with enough security clearance to work with the high-tech photographic equipment which processed information from U-2 spy planes, and other military intelligence hardware.

Mr Wolfe described a top secret meeting, during which new lunar photographs were being looked at from the dark side of the moon in 1965.

He said: "I was in a colour lab one day when my boss, Staff Sergeant Taylor, came over to me and said that they were having a problem with some equipment on the base and it was the first lunar orbiter program, where they had a mission to pretty much locate the first landing sites for the 1969 lunar mission for the astronauts."

He said a dark room attendant explained that recent enhanced images had clearly shown structures on the surface of the dark side of the Moon.

He said: "They were structures that were definitely not created by natural means, such as meteors, or ancient collisions with other heavenly bodies.