The mysterious illness has left the security establishment in the USA deeply concerned after a number of spies and diplomates fell ill around the world. Termed 'Havana syndrome' after the American embassy which first reported cases, the cause of the neurological disorders illness remains unsolved. Security experts have pointed to the possibility of the incidents being caused by an as yet unidentified weapon that may admit pluses of microwaves or "directed" radiofrequency.

       "It is real," former CIA officer Marc Polymeropoulos told the BBC.

       "We need to get our people healthcare.

       "Then we need to find out who's doing this.

       "Because as I have always said this is an act of war."

       Havana Syndrome cases have been reported across the globe, last month US officials in Berlin reported symptoms.

       US diplomats stationed in Germany required medical attention after suffering from nausea, severe headaches, ear pain, fatigue, insomnia, and sluggishness.

       Speaking at the time, Timothy Barrett, the assistant director of national intelligence for strategic communications, said: “This is a top priority for the intelligence community."

       He added: “And we are supporting the NSC-led effort to get answers, take care of our people and prevent future incidents.”

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