A FAMOUS UFO whistle-blower who claimed he saw top secret Nasa photos showing "alien structures" on the moon has died in a horror bike accident.

Former US Air Force Sergeant Karl Wolfe, 74, was cycling in Lansing, New York, when he was hit by a tractor trailer.

He was rushed to nearby Cayuga Medical Centre but later died from his injuries.

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Cops have launched a probe into his death but no charges have been filed against the driver.

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Wolfe shot to fame in 2001 when he made startling claims that Nasa was covering up evidence of artificial structures on the dark side of the moon.

Sergeant Wolfe had a top secret clearance and worked with the tactical air command at Langley Air Force base in Virginia.

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This story originally appeared in The Sun. For more from The Sun, click here