The possible discovery of wreckage from MH370 has sent conspiracy theorists into overdrive.

Some have claimed its location proves their version of events, while others have discredited the plane part as a fake they say was “planted” by authorities as part of the wider cover-up.

The theories started shortly after the discovery was announced late on Wednesday night, as several people had predicted.

One of the most persistent conspiracy theories is that the Malaysia Airlines flight was taken towards Diego Garcia, a British territory in the middle of the Indian Ocean hosting a large US military base.

Some proponents claim it landed there, while others claim it was shot down as it neared because of fears of a terror attack.

Diego Garcia is 1,475 miles away from Réunion, making the appearance of possible MH370 debris on the remote island an exciting prospect for those believing it was attacked.

The Diego Garcia theorists are taking the debris as possible proof MH370 was shot down (Reuters)

For theorists believing the plane had landed intact on Diego Garcia, Malaysia, a desert island, or Kazakhstan, the beach discovery was less welcome.

Many people quickly dismissed the chunk of metal, believed to be a Boeing 777 wing component called a flaperon, as a fake.

Some said it was planted by Malaysian authorities to calm the anger of relatives of the 239 people on board, who have lodged several legal cases over the disaster.

There is also continuing speculation over an item of supposedly “mystery cargo”.

According to an email sent to this newspaper, MH370 was carrying a nuclear warhead to North Korea and the US authorised the Thai military to shoot it down, prompting an international cover-up.

Or it could still be aliens.

Oceanographers say the arrival of MH370 debris in Réunion would conform to the expected path of ocean currents from the point in its flight path where it was believed to have crashed.

Professor Charitha Pattiaratchi, from the University of Western Australia, conducted current modelling that predicted MH370 debris might reach Reunion.

Writing for The Independent, he said that the flaperon would discredit theories the plane had been stolen by terrorist groups or rogue governments and landed in a secret location.

"Of course the discovery of debris, if proven to belong to MH370, would debunk this sort of speculation," the professor said.

"Even if there were an intended destination and a wider conspiratorial plan, the fact that the debris had washed up on Réunion Island would mean that the plane had to have come down in the southern hemisphere. "

The debris has been flown to France to be examined by specialists in Toulouse, who are seeking to establish whether it came from a Boeing 777 and if that plane was the missing Malaysia Airlines aircraft.