In testimony published Thursday, Luís Zúñiga – a Cuban dissident who spent 19 years in political prison – detailed his experience seeing the use of “acoustic attacks” on political prisoners to damage their brains and ultimately kill them. His testimony described a tool that resembled theories of how some U.S. diplomats may have been severely injured by sonic devices in Havana.

In a briefing Thursday, the U.S. State Department confirmed that at least 16 U.S. diplomats suffered a variety of physical symptoms doctors believe were prompted by a sophisticated “sonic” device. Multiple news outlets have reported that the symptoms vary from headaches and vomiting to more severe issues like permanent hearing loss and brain damage.

Zúñiga testified to watching Cuban state police kill a man with sonic torture. The Miami-based Cuban Democratic Directorate issued a statement regarding his testimony arguing that acoustic attacks were “not alien to the Castro agenda.” They cited Zúñiga’s testimony, delivered on July 15 to Justice Cuba, as proof that others had witnessed such incidents on the island.

According to Zúñiga, prison guards would place large speakers near the cells and broadcast “a sound that was like short-wave radio when it was not set on any particular station and would emit shrill sounds.”

“The torture would go on all day and night and … ended when a prisoner, Rafael Del Pino Siero, died,” he noted. “Since we were in individual cells, nobody could know if he hung himself or he was hanged, but the truth is he died under torture.”

The former political prisoner detailed a variety of incidents of torture that he witnessed both in prisons like Combinado del Este, notorious as a torture ward for political dissidents, and “psychiatric facilities” like the institution informally known as “Mazorra,” where dissidents would receive electroshock torture.

“I was a victim and witness to innumerable cases of torture, cruel and inhuman treatment, mutilations,” he told those convened, noting that some prisons were mixed gender and women could be heard receiving severe beatings from men in their cells.

“They beat all political prisoners … systematically, because the goal was not just to punish you for rebelling or opposing the communist dictatorship, but to destroy your soul, subject your spirit, humble you, turn you into almost an animal,” he asserted.

“That was the official, systematic policy of prisons.”

Denuncia expreso político cubano Luís Zúñiga ante Justice Cuba: https://t.co/7BQ5WGDKZx via @YouTube — Directorio (@DirectorioCuba) August 24, 2017

Zúñiga testified to seeing a guard cut half of a prisoner’s hand off with a machete for complaining about the quality of the food and hearing of a man forced into electroshock torture at Mazorra for having relayed confidential information he heard guards discussing to outsiders. “He received 14 sessions of electroshock: five in the head and ten in the testicles,” Zúñiga declared.

Mazorra is the location currently holding Daniel Llorente, a Cuban dissident who was detained after daring to wave an American flag at a communist parade in May.

Zúñiga’s testimony serves as both a reminder of the Castro regime’s brutality and its history of using torture against its enemies. The anecdotes about aural torture appear to give credence to the fact that the Cuban government possesses devices capable of using sonic technologies to hurt people.

The State Department confirmed on Thursday that “at least 16 U.S. Government employees, members of our embassy community, have experienced some kind of symptoms” as a result of “unprecedented” “incidents” in Havana. “We take this situation extremely seriously,” she noted. “We are trying to provide them the help, the medical care, the treatment, and the support that they need and the support that they deserve.”

Spokeswoman Heather Nauert told reporters the “incidents are no longer occurring” but could not offer proof of an end to these attacks when asked to establish why the United States believed this to be so. In particular, Nauert noted that American investigators had not been able to pinpoint the damage to “a piece of equipment” or a location.

Some diplomats suffering symptoms are still in Cuba, Nauert confirmed.

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