An intelligence report by a panel of experts said on Wednesday, 2 February, that "Havana Syndrome" which affected several US officials, diplomats and spies, could have been caused by ultrasound or pulsed electromagnetic energy from an external source.

Despite the CIA stating that fears of the incidents being connected to a foreign power were unfounded, this report says around 24 cases out of approximately 2,000 reported incidents couldn't be attributed to any environmental or psychological cause.

The report states that devices could exist capable of emitting pulsed electromagnetic energy which could trigger the health effects observed in these cases, stating that they could be a plausible cause.

The report adds that devices exist with "modest energy requirements" which could be concealable and also produce the symptoms witnessed in these AHIs.

Both, National Intelligence Director Avril Haines and the CIA's Director, William Burns added that while the investigation was not focused on identifying the culprit, it could help them to identify the origins of the ailments.

To identify a case,the panel narrowed the problem by focusing on four core characteristics:

• The acute onset of audio-vestibular sensory phenomena which includes sound or pressure in one ear

• Vertigo, loss of balance and ear pain

• A “strong sense of locality or directionality”

• The absence of known environmental or medical conditions that might cause the reported mysterious signs and symptoms.

The symptoms date the earliest cases reported to 2016.

The report also added that "sources exist that could generate the required stimulus, are concealable, and have moderate power requirements."

However, the expert panel report also stated that there was a dearth of research on the effects of pulsed electromagnetic energy on humans, reports The Guardian.

On Wednesday, 2 February, a victims group issued a statement arguing that the new report by the expert panel, "reinforces the need for the intelligence community and the US government to increase their efforts to have a better understanding of the causes of Havana Syndrome".

(Written with inputs from The Guardian.)