A veteran CIA officer who helped the agency track down Osama Bin Laden has reportedly been chosen to lead the agency’s investigation of what’s behind a pattern of illnesses among U.S. diplomatic and intelligence personnel that may be the result of radio frequency attacks launched by hostile actors.

Sources familiar with the decision told the Wall Street Journal on Wednesday that CIA Director William Burns chose this veteran of the hunt for Bin Laden. The CIA officer, whose identity remains concealed, is part of what agency officials said was a growing effort to determine the source of the apparent attacks, which have caused an illness that has come to be known as “Havana Syndrome.”

Havana Syndrome got its name after U.S. diplomatic personnel at the U.S. Embassy in Havana, Cuba began developing headaches, nausea and other concerning symptoms after experiencing what they described as a sensation of heat and pressure and hearing a grating sound in 2016. Following the 2016 attacks, similar incidents were reported in China, Russia, Syria, Austria and even in the U.S.

Initial efforts to determine the cause of the illness have not formed a definitive answer. One study said the piercing sound Havana embassy employees heard may have just been that of the Indies short-tailed cricket.

The CIA officer now chosen to lead the Havana Syndrome investigation is taking over the task force after CIA officer Cynthia Rapp delayed her retirement to help form the task force. The new leader of the task force is a veteran of the CIA’s Counterterrorism Center and, according to one official, spent more than a decade tracking Bin Laden and his wider Al Qaeda terrorist network.

“Bin Laden, you could argue, was different—we knew what the target was,” the official told the Wall Street Journal. The exact cause or culprits behind Havana Syndrome, by contrast, remains a mystery.

In December, the National Academies of Sciences, Engineering and Medicine determined that the illnesses of American diplomats working at the U.S. Embassy in Havana, Cuba, in late 2016 and the U.S. Consulate in Guangzhou, China, in early 2017, are likely the result of a radio frequency attack.

The CIA task force investigating the Havana Syndrome case was formed last December and is composed of specialists from across the agency. An official told the Wall Street Journal the task force includes intelligence analysts, clandestine officers who collect human intelligence, clinicians and human resource specialists.

Marc Polymeropoulos, a veteran CIA officer who retired from the agency after experiencing severe Havana Syndrome symptoms after a trip to Moscow, praised the new efforts to investigate what caused his sickness.

Polymeropoulos has been critical of the initial efforts by the agency to investigate Havan Syndrome’s causes, but told the Wall Street Journal, “There’s been a sea change in the agency’s view towards these anomalous health incidents since Director Burns took over. He’s dedicating appropriate resources and top-notch personnel.”