The CIA has released an interim finding after investigating several incidents involving U.S. intelligence personnel who reported cases of "Havana syndrome."
The agency said it doesn't believe that Russia or other foreign adversaries used some directed energy weapon to harm American diplomats and intelligence officers who reported suffering symptoms from the mysterious illness, the Associated Press reported.
The illness was given its name in 2016 after U.S. government employees reported they suffered symptoms, including headaches, vertigo, blurry vision, and brain injuries, in the Cuba capital.
The agency said in the cases they reviewed, they found that most of them can be explained by factors like previously undiagnosed medical conditions, NBC News reported.
Some cases are still being investigated, the news outlets reported.