(CNN) — When a number of US diplomats and their families in Cuba reported hearing bizarre noises in 2016 and 2017-- and experienced a range of symptoms such as dizziness, vertigo, and pain and ringing in the ears -- US Department of State officials feared they might have fallen victim to an "acoustic attack" by sonic devices.
In October 2017, the Associated Press obtained and released the first publicly reported audio sample said to be related to the incidents. But US officials have been unable to definitively identify the source or cause of the symptoms, and Cuban officials have denied any attack.
But now, after analyzing the recording, scientists say the source of the piercing noise said to be a "sonic attack" -- described by the diplomats' as "buzzing," "grinding metal" and "piercing squeals" -- could be an echoing call of a cricket. Specifically, the Indies short-tailed cricket, Anurogryllus celerinictus.
In research released on January 4, a British and an American scientist said the cricket's chirps matched "in nuanced detail, the AP recording in duration, pulse repetition rate, power spectrum, pulse rate stability, and oscillations per pulse." The research has not been peer-reviewed.
The scientists said inconsistencies in the AP-released recording might be because it was made indoors, while insects are typically recorded in the field, they wrote.