Mystery health attacks 'targeted US spy network in Cuba'
Mysterious attacks on the health of US personnel in Havana have struck at the heart of America's spy network in Cuba, with intelligence operatives among the first and most severely affected victims, sources said.
The attacks did not emerge until US spies working under diplomatic cover reported hearing bizarre sounds and experiencing even stranger physical effects.
The attacks started within days of President Donald Trump's surprise election last November.
However, the precise timeline remains unclear, including whether intelligence officers were the first victims to experience the effects, or merely the first victims to report it.
US officials said the situation "ongoing".
The American state department and the CIA declined to comment on whether intelligence officers had been affected.
To date, the Trump administration has described the 21 victims as US embassy personnel or "members of the diplomatic community".
That description suggested only bona fide diplomats and their family members were struck, with no logical motivation beyond disrupting US-Cuban relations.
Behind the scenes, though, investigators immediately started searching for explanations in the darker world of spycraft and counter-espionage, given that so many of the first reported cases involved intelligence workers posted to the US embassy.
That revelation, confirmed by several officials, adds yet another element of mystery to a year-long saga which the Trump administration said may not be over.
Of the 21 confirmed cases, American spies suffered some of the most acute damage, including brain injury and hearing loss which has not healed, said several US officials.
They heard an unsettling sound inside and in some cases outside their Havana homes, described as similar to loud crickets. Then they fell ill.
Over time, the attacks seemed to evolve.
In many of the more recent cases, victims did not hear noises and were not aware an attack was occurring, identifying the symptoms only later.
This has raised concerns among investigators that the attacks may be getting more sophisticated and harder to detect.
Though the State Department has called all the cases "medically confirmed", several US officials said it is unclear whether all of the victims' symptoms can be conclusively tied to attacks.
Considering the deep sense of alarm among Americans working in the embassy, it is possible some workers attributed unrelated illnesses to attacks.