Aliens came to Earth to stop a nuclear war between America and Russia, according the bizarre claim of a former astronaut.

Edgar Mitchell, the sixth man to walk on the moon, says high-ranking military officials witnessed alien ships during weapons tests throughout the 1940s.

The UFOs, he says, were spotted hovering over the world's first nuclear weapons test which took place on July 16, 1945 in the desolate White Sands deserts of New Mexico.

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Edgar Mitchell (left), the sixth man to walk on the moon, says high-ranking military sources witness alien ships hovering during weapons tests. The UFOs, he says, were seen during the world's first nuclear weapons test which took place on July 16, 1945 in the desolate White Sands deserts of New Mexico

The Nasa veteran has regularly spoken about his belief in aliens ever since he landed on the surface of the moon during the Apollo 14 mission in 1971.

'White Sands was a testing ground for atomic weapons - and that's what the extra-terrestrials were interested in,' the 84-year-old Texan told Mirror Online.

'They wanted to know about our military capabilities.

'My own experience talking to people has made it clear the ETs had been attempting to keep us from going to war and help create peace on Earth.'

Dr Mitchell says stories from people who manned missile bases during the 20th Century back up his claims.

Edgar Mitchell, a veteran of the Apollo 14 mission in 1971, says stories from people who manned missile bases during the 20th Century back up his claims. 'Other officers from bases on the Pacific coast told me their [test] missiles were frequently shot down by alien spacecraft,' he said

'Other officers from bases on the Pacific coast told me their [test] missiles were frequently shot down by alien spacecraft,' he said.

He previously said supposedly real-life ET's were similar to the traditional image of a small frame, large eyes and head.

He claimed our technology is 'not nearly as sophisticated' as theirs and 'had they been hostile', he warned 'we would be been gone by now'.

Nick Pope, a former Ministry of Defence UFO researcher, told DailyMail.com that Dr Mitchell's comments are all based on second-hand reports.

'Even where Mitchell's sources are genuine, how do we know they have access to classified information about UFOs?' asks Pope.

'White Sands was a testing ground for atomic weapons - and that's what the extra-terrestrials were interested in,' the 84-year-old told Mirror Online. 'My own experience talking to people has made it clear the ETs had been attempting to keep us from going to war and help create peace on Earth.'

UFO believers say it's no coincidence that aliens showed up very shortly after we'd developed atomic weapons and rocket technology, as this is when they were alerted to the threat we pose to the wider cosmos.

'Ironically, governments have sometimes secretly promoted belief in UFOs, because if someone sees a secret prototype aircraft or drone, it's much better to have it reported as a flying saucer than recognised for what it is,' said Pope.

'None of this is to say that there haven't been some genuinely fascinating and unexplained UFO sightings around nuclear facilities and military bases, but just because a UFO sighting is unexplained, it doesn't follow that it's extraterrestrial.'

'In a final irony, the very conspiracy theorists who believe Edgar Mitchell when he talks about aliens don't believe him when he talks about his moon mission, because they think it was all done on a film set.'

This image was taken during the Apollo 14 mission in February 1971 of US astronauts Alan Shepard (left) and Edgar Mitchell (right). The Apollo XIV mission, the third mission to land on the moon, was launched on January 31, 1971 and landed on the moon on February 5, 1971

Dr Mitchell, who has a Bachelor of Science degree in aeronautical engineering and a Doctor of Science degree in Aeronautics and Astronautics also says the Roswell cover up was real.

'This is really starting to open up,' he told a radio show several years ago. 'I think we're headed for real disclosure and some serious organisations are moving in that direction.'

Officials from Nasa were quick to play the comments down.

In a statement at the time, a spokesman said: 'Nasa does not track UFOs. Nasa is not involved in any sort of cover up about alien life on this planet or anywhere in the universe.

'Dr Mitchell is a great American, but we do not share his opinions on this issue.'