The Defense Department has spent more than a year examining a device bought during an undercover operation—one that some investigators believe could be connected to the cluster of unexplained ailments reported by US spies, diplomats and troops, often referred to as Havana Syndrome, according to four people briefed on the matter.
A division of the Department of Homeland Security, Homeland Security Investigations, purchased the device for millions of dollars near the end of the Biden administration using Defense Department funds, two of the sources said. Officials paid “eight figures” for it, they added, without providing a more exact figure.
The device remains under study, and officials continue to disagree—while some corners of government remain skeptical—about whether it is linked to the dozens of anomalous health incidents that are still officially unresolved.
One source said the device emits pulsed radio waves, a mechanism that some officials and academics have long suggested could be involved in the incidents. While the device is not entirely Russian in origin, the source said it includes Russian components.
A key question has persisted for years: how a system powerful enough to cause the kinds of effects reported by some victims could also be portable. That issue remains central to the current inquiry, one person briefed on the device said, adding that the device could fit inside a backpack.
The purchase has reignited a long-running, often bitter dispute within the US government over the cause of these episodes, officially described as “anomalous health episodes.”
The mystery first came into focus in late 2016, when a group of US diplomats in Havana reported symptoms consistent with head trauma, including vertigo and severe headaches. In the years that followed, additional cases were reported in multiple countries.
Over the past decade, US intelligence and defense officials have tried to determine whether those affected were targeted by a foreign government using some form of directed energy. Senior intelligence officials have said publicly that the evidence has not supported that conclusion. Victims, however, have argued they were dismissed and that key indicators—particularly those pointing toward Russia—were not taken seriously.
Even so, defense officials viewed the matter as significant enough to brief the House and Senate Intelligence Committees late last year, sources said, including discussion of the acquired device and the testing underway.
Some officials now worry that if the technology is shown to be viable, it may have spread beyond a single actor, several sources said—raising the possibility that more than one country could have access to a device capable of causing career-ending injuries to US personnel.
CNN could not determine where—or from whom—HSI obtained the device. HSI has a history of working with the Defense Department on global operations and has broad authority to investigate crimes tied to customs violations, including probes into the overseas spread of US-controlled technology or expertise.
Those proliferation investigations are “the single biggest collaboration point between HSI and the US military,” according to a former Homeland Security official.
For instance, when the US military encountered US technology in Afghanistan or Iraq and questions arose about how those components reached the region, it would often involve HSI, the former official said.
It is also unclear how the US government first learned about the device’s existence, enabling the undercover purchase. The broader issue has remained stubbornly murky for both intelligence and medical experts.
One challenge for the medical community is the lack of a consistent definition of what qualifies as an anomalous health incident, or AHI. In some cases, testing took place long after symptoms began, making it harder to determine what physical changes, if any, occurred at the time.
In 2022, an intelligence panel looking into AHIs said that some episodes could “plausibly” have been caused by “pulsed electromagnetic energy” from an external source.
But in 2023, the intelligence community said publicly it could not link any cases to a foreign adversary, and assessed it was unlikely the illness resulted from a targeted campaign. As recently as January 2025, that broader assessment remained that it was very unlikely symptoms were caused by a foreign actor—though an official with the Office of the Director of National Intelligence emphasized analysts could not “rule out” the possibility in a small number of cases.
That position has angered many victims, some of whom believe intelligence exists that directly implicates Russia. Several have reported symptoms severe enough to force them out of service.
Some current and former CIA officers have also raised concerns that the agency downplayed its investigation, CNN has previously reported.
For some victims, news of the device purchase has felt like potential validation.
“If the [US government] has indeed uncovered such devices, then the CIA owes all the victims a major and public apology for how we have been treated as pariahs,” Marc Polymeropoulos, one of the first CIA officers to publicly describe injuries he says he sustained during an attack in Moscow in 2017, said in a statement to CNN.
