Theories on the missing MH370 not only sparked conspiracies and cover-ups involving the Malaysian government. In a larger context, the MH370 brought into spotlight a grand intertwined plot involving the biggest and most powerful governments - the U.S. and the UK.

For years, the British government had denied claims of its permission granted for the U.S. to use Diego Garcia for CIA "activities" dubbed as "rendition" program.

But a controversial theory claimed the MH370 was taken in secrecy and being held in the place as part of a false flag attack likened to the 9/11 bombing.

As a result, the spotlight was now shifted to Diego Garcia as where CIA was allegedly running a black jail for Al-Qaeda suspects. This claim was reportedly backed-up by leaked 500-page documents from the U.S. Senate investigation on CIA's alleged kidnap and torture activities following 9/11.

In a report from The Telegraph, Reprieve, a charity representing those victims of CIA alleged tortures, urged the British government to come clean in the allegation that it allowed the U.S. to conduct inhumane activities within the British soil.

"We need to know immediately whether ministers misled Parliament over CIA torture on British soil. If the CIA operated a black site on Diego Garcia, then a string of official statements, from both this and the last government, were totally false. Were ministers asleep at the wheel? Or, as the report suggests, have we been lied to for years? " Cori Crider, Reprieve's strategic director, said.

To date, the leaked documents were now in the custody of the White House which assured public that it would be releasing a copy of the documents in the coming days.

According to the data obtained by The Telegraph from an unnamed source, ex-prime minister Tony Blair and other senior government ministers were knowledgeable of the CIA program in Diego Garcia.

As early as 2006, there had been reports circulating about the covert CIA activities being conducted in Diego Garcia. In 2011, classified documents, dubbed as the Tripoli Documents, revealed Diego Garcia as one place considered for Libyan Islamist Abdel-Hakim Belhadj and his wife Fatima Boudchar to undergo "rendition" back in March of 2004.

The British government through David Lidington, a minister of state at the Foreign Office, denied the information contained in the Tripoli Documents in December 2012.

"No flights with a detainee on board landed on Diego Garcia in March 2004... no other instances in which US intelligence flights landed in the UK, our Overseas Territories, or the Crown Dependencies, with a detainee, on board since 11 September 2001," Lidington said in a statement to the Parliament.

In its response to Reprieve's inquiry for the British government to come clean from the allegations, the British government referred back to the statement of December 2012.

With this old issue surrounding Diego Garcia resurfacing, conspiracists insisted MH370 is one part of a grand plot which full detail and objective remains unknown.

With Australia leading the search for the missing plane, what is its involvement in the grand picture? Conspiracists claimed Australia's participation was to mislead the attention away from Diego Garcia.

Ever since Australia led the search, Prime Minister Tony Abbott had come up of announcements of promising leads that bright orange objects afloat Indian Ocean and pings. But each time search operatives came back, it had no positive results.

Dr. Kevin Barrett, an Arabist-Islamologist, one of America's best-known critics of the War on Terror, highlighted a dubious aspect with how Australia is handling the search.

Barrett is also the co-founder of the Muslim-Christian-Jewish Alliance, and author of the books Truth Jihad: My Epic Struggle Against the 9/11 Big Lie (2007) and Questioning the War on Terror: A Primer for Obama Voters (2009).

"This aircraft cannot be just lost. It cannot have just disappeared. This makes no sense. The CIA base in Alice Springs Australia knows precisely what happened to that plane. And it is interesting the Malaysian government has asked them and they are not getting any response. There is obviously a cover-up," Barret said during an interview with Iran's Press TV channel.

"It is simply unthinkable that this plane would simply turn, fly off in the wrong direction, be spotted over the Maldives Islands heading for Diego Garcia and just disappear. It is something very strange that has happened to this plane."