"Two individuals from the US Embassy in Havana are undergoing medical evaluation," the official said. "These are potentially new cases, but they are not yet medically-confirmed."
The official explained that out of privacy considerations, no further details could be provided, but noted that an update will be provided when the medical evaluations are complete.
Twenty-one US diplomats in Cuba were affected last August by sonic attacks with an acoustic device, according to the State Department. Media reports said some of the diplomats suffered permanent hearing loss and possible brain injuries as a result of attacks with a sonic weapon.
More recently, US diplomats in China also complained of symptoms similar to the ones suffered by colleagues in Cuba.
On Tuesday, US Secretary of State Mike Pompeo announced that the State Department established a task force to respond to the mysterious acoustic incidents overseas.