At least 16 Americans in Cuba have experienced symptoms as a result of the acoustic attacks on diplomats, State Department spokeswoman Heather Nauert said in the first public confirmation of the number of people affected. Medical records reviewed by CBS News Wednesday revealed that the U.S. diplomats were diagnosed with conditions as serious as “mild traumatic brain injury” with “likely damage to the central nervous system.”

While the episode has been described as “unprecedented” by the State Department, some experts remain skeptical regarding the use of sonic weapons. Citing a source familiar with the incidents, CBS said officials are investigating whether the diplomats were targets of some form of sonic attack directed at their homes. Cuban officials have denied directing any actions against the U.S. government employees and have launched their own investigation into the incidents. “It was not immediately clear if the device was a weapon used in a deliberate attack, or had some other purpose.”

The State Department retaliated in late May by expelling two Cuban diplomats from their embassy in Washington D.C. – a move condemned by Cuba at the time as “unjustified and baseless.”

“Cuba has never permitted, nor will permit, that Cuban territory be used for any action against accredited diplomatic officials or their families, with no exception,” the Cuban government said in early August.
The United States State Department says at least 16 U.S. government employees and family members based in Cuba showed physical symptoms from the previously reported acoustic attacks. Investigators are exploring whether some form of sonic attack was directed at diplomats' homes.