Cuba mystery: What theories U.S. investigators are pursuing

WASHINGTON—There must be an answer. Whatever is harming U.S. diplomats in Havana, it’s eluded the doctors, scientists and intelligence analysts scouring for answers. Investigators have chased many theories, including a sonic attack, electromagnetic weapon or flawed spying device.

Each explanation seems to fit parts of what’s happened, conflicting with others.

The United States doesn’t even know what to call it. Secretary of State Rex Tillerson used the phrase “health attacks.” The State Department prefers “incidents.”

Either way, suspicion has fallen on Cuba. But investigators also are examining whether a rogue faction of its security services, another country such as Russia, or some combination is to blame, more than a dozen U.S. officials familiar with the investigation told The Associated Press.

Those officials spoke on condition of anonymity because they weren’t authorized to publicly discuss the investigation. The AP also talked to scientists, physicians, acoustics and weapons experts and others about the theories being pursued.

Perhaps the biggest mystery is why the symptoms, sounds and sensations vary so dramatically from person to person.

Of the 21 medically confirmed U.S. victims, some have permanent hearing loss or concussions, while others suffered nausea, headaches and ear-ringing. Some are struggling with concentration or common word recall, the AP has reported. Some felt vibrations or heard loud sounds mysteriously audible in only parts of rooms , and others heard nothing.

“These are very nonspecific symptoms. That’s why it’s difficult to tell what’s going on,” said Dr. H. Jeffrey Kim, a specialist on ear disorders at MedStar Georgetown University Hospital who isn’t involved with the investigation.

To solve the puzzle, investigators are sorting symptoms into categories, such as auditory and neurological, according to individuals briefed on the probe.

There can be a lag before victims discover or report symptoms, some of which are hard to diagnose. So investigators are charting the timeline of reported incidents to identify “clusters” to help solve the when, where and how of the Havana whodunit.

While Cuba has been surprisingly cooperative, even inviting the FBI to fly down to Havana, it’s not the same as an investigation with the U.S. government in full control.

“You’re on foreign soil,” said David Rubincam, a former FBI agent who served in Moscow. “The quality of the information and evidence you collect is limited to what the host government will allow you to see and hear and touch and do.”

Especially when you don’t even know what you’re looking for.