A former airline boss and writer claims the U.S. downed Malaysia Airlines flight MH370 because the military feared it had been taken over by hackers and was about to be used in a 9/11-style attack.

Marc Dugain, the former chief executive of now-defunct Proteus Airlines, said the jumbo jet was shot down near a U.S. military base on the remote island of Diego Garcia in the Indian Ocean after it was hacked.

He told Paris Match that islanders in the Maldives near Diego Garcia told him they saw the missing aircraft flying low.

Dugain spoke of a fisherman on a small island who spoke of a 'huge plane' in Malaysie Airline's colours on March 8.

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Theory: Marc Dugain, the former chief executive of now-defunct Proteus Airlines, said Malaysia Airlines flight MH370 was shot down near a U.S. military base

The former airline exec told Paris Match that islanders in the Maldives near Diego Garcia told him they saw the missing aircraft flying low.

He also said islanders had found an empty fire extinguisher from the plane in the water near Baarah island.

The Senegal-born Frenchman, who is now a successful novelist, also told a radio station he was warned not to investigate MH370 by an intelligence source, who spoke of 'risks' and counselled him to 'let time do its work'.

Last week grieving family members of Chinese passengers from a missing Malaysia Airlines flight protested outside the foreign ministry in Beijing Friday accusing the government of failing to provide them with regular updates on the search for the aircraft.

About 30 people, many of them elderly, gathered at the gates of the ministry with temperatures approaching freezing and were confronted by a line of police.

The U.S. Navy Support Facility at Diego Garcia, British Indian Ocean Territory. Dugain claims the U.S. feared the plane was about to be used in a terror outrage

Leading Seaman, Boatswain's Mate, William Sharkey searches for debris on a rigid hull inflatable boat in the Southern Indian Ocean in April. In the background is HMAS Perth, which was involved in the search

They demanded to speak to government officials in a bid to get more information on the search for flight MH370. Police manhandled and pushed protesters that attempted to enter the gate and warned passersby to leave the area immediately.

'My son is alive and I want to know what the government is doing to find him,' said Liu Dianyun, the mother of one of the passengers.

Some drove for two hours to attend the demonstration, despite acknowledging that their efforts were unlikely to produce results.

Chinese passengers account for about two-thirds of the 239 people who were aboard the Boeing 777, which vanished on March 8 en route from Kuala Lumpur to China's capital.

Dozens of their relatives were reportedly beaten and arrested earlier this year.