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TAMPA (FOX 13) - Over the past several months, 21 U.S. Embassy employees have suffered a variety of injuries from attacks of an unknown nature.
The U.S State Department says the employees have reported a range of physical symptoms including ear pain, hearing loss, dizziness, headache, fatigue, cognitive issues, and difficulty sleeping.
Investigators have been unable to determine who is responsible, or what is causing these apparent auditory attacks.
On September 29, the department ordered non-emergency personnel assigned to the U.S. Embassy in Havana, and their family members, to leave Cuba.
In a statement, the State Department said, "Until the Government of Cuba can ensure the safety of our diplomats in Cuba, our Embassy will be reduced to emergency personnel in order to minimize the number of diplomats at risk of exposure to harm."
The State Department also issued a travel warning - telling U.S. citizens to avoid travel to Cuba.
There have been no reports of private U.S. citizens being targeted, but the attacks are known to have happened in U.S. diplomatic residences and hotels frequented by U.S. citizens.
"The health, safety, and well-being of our Embassy community is our greatest concern. We will continue to aggressively investigate these attacks until the matter is resolved," the department said.