A host of wild theories including a Taliban hijack or meteor strike had emerged to fill the information vacuum in the days following the plane's disappearance on March 8 with 239 aboard as authorities across Asia scrambled to figure out what happened.
The speculation abated after Malaysia said in late March the plane was believed to have gone down in the Indian Ocean for unknown reasons, but has revived due to the failure of an international search effort to find any trace of the plane.
The still-influential Mahathir, 88, said the US Central Intelligence Agency might have taken control of the American-made plane after it was commandeered by terrorists, adding it was possible "the plane is somewhere, maybe without MAS (Malaysia Airlines) markings".
"Can it not be that the pilot of MH370 lost control of their aircraft after someone directly or remotely activated the equipment for seizure of control of the aircraft?" Mahathir wrote.
Also Read
Similar allegations were floated previously by a newspaper controlled by Malaysia's ruling party -- which was under fire over a perceived bumbling and secretive handling of the crisis.
The suggestion of American involvement was dismissed at the time by the US embassy in Malaysia.
Two films about MH370 were touted Sunday to potential distributors at the Cannes Film Festival in France, with a trailer for one of them -- "The Vanishing Act" -- showing terrified passengers and a gun being brandished.
One of the first books about MH370 went on sale yesterday, suggesting it could have been shot down during a military drill in the South China Sea and the incident covered-up.