DECLASSIFIED documents have revealed fears that Russia sabotaged NASA during the Cold War and was to blame for US space disasters including the Challenger shuttle explosion.

Astonishing secret letters sent to top CIA officials in 1986 called for an investigation into Soviet involvement in several launch catastrophes.

6 The Challenger rocket breaks apart and explodes 73 seconds after take off in 1986 Credit: AP:Associated Press

6 A 1986 NASA file photo of the Challenger space shuttle crew Credit: AP:Associated Press

The letters were sent by US Army lieutenant general Daniel O. Graham - a former deputy director of the CIA, and ex-military adviser to US President Ronald Reagan.

His previously classified correspondence with CIA director William Casey includes serious warnings that the "case for Soviet sabotage of our space program is too strong to be ignored".

Lt Gen Graham raised concerns about back-to-back NASA launch failures including the Titan 34D, Ariane 3, Nike Orion, Delta 3914, the Daily Star reports.

He made particular reference to the Challenger shuttle, which broke apart 73 seconds after take off and exploded - killing all seven astronauts on board.

Claims that the space program disasters were down to Soviet Union sabotage were not proven following enquiries into each incident.

My experts calculate the odds against this being coincidence, given the reliability records of the systems involved are 250 million to one. US Army lieutenant general Daniel O. Graham

In the letter dated July 23, 1986, Lt Gen Graham suggested failure to investigate potential Soviet involvement could amount to a "cover up".

He wrote: "The basic fact is that the West has had a series of catastrophes with space vehicles beginning in August 1985.

"My experts calculate the odds against this being coincidence, given the reliability records of the systems involved are 250 million to one.

"The notion that this is due to a rash of ineptitude might hold up if only NASA was involved, but the fact is there were four launch organizations involved.

"It defies logic to assume they all went sour together."

Lt Gen Graham, who was awarded the Distinguished Intelligence Medal, also raised suspicions over the catastrophic challenger launch.



'SERIOUS PROBE' INTO RUSSIAN INVOLVEMENT NEEDED

He observed the Soviets had not deployed any normal surveillance flights over the rocket, suggesting "foul play" was afoot.

Additionally, he claimed the "extraordinarily quick response" from Russia to offer condolences was peculiar.

Although he admitted his suspicions did not "add up to proof of Soviet sabotage", he noted that Russia had the power to "ground" the NASA.

In the letter, sent to White House officers, Lt Gen Graham called for a "serious probe" into Russian meddling and urged for security improvements at Cape Canaveral.

He warned it would be easy for a "sniper" to get amongst thousands of spectators watching the Challenger launch.

The letter continued: "While sabotage is not high on most observers' lists of possible explanations of the Challengers tragedy (including mine), it should not now be excluded from anyone's list of possibilities."

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An enquiry into the tragedy found that NASA was to blame after it failed to follow safety procedures.

Official records state the explosion that destroyed the Challenger was caused by faulty seals that were not spotted during safety checks.

This led to the shuttle program being halted for 32 months.

6 The declassified letter sent to CIA bosses by US Army lieutenant general Daniel O. Graham revealing fears of soviet sabotage Credit: CIA

6 A reply to his letter said 'the shuttle is hated by America's enemies as it is admired by America and its friends' Credit: CIA

6 The challenger shuttle lifts off from the Kennedy Space Centre on its doomed 1986 flight Credit: Getty - Contributor

6 All seven crew members were killed when the Challenger exploded mid flight, with NASA blaming faulty seals Credit: AP:Associated Press

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