President Donald Trump said today he holds the Cuban government responsible for the mysterious auditory attacks that have made more than a dozen American diplomats in Havana sick over the past several months.

“I do believe Cuba’s responsible. I believe that,” Trump told reporters. Trump didn’t clarify whether he believed the Cuban government actually launched the attacks or if he believes Cuba bears ultimate responsibility for the health of American diplomats there, which other U.S. officials have said.

The audio apparently sounds like crickets, some kind of high-pitched whine, according to The Associated Press, which obtained a copy of the tape. “There are multiple, distinct tones that sound to some like they’re colliding in a nails-on-the-chalkboard effect,” the AP reported Friday.

The State Department said in late September that 21 embassy employees “have suffered a variety of injuries from attacks of an unknown nature.”