As many as three dozen current and former CIA officers have gone to the House and Senate Intelligence Committees over the past year to raise concerns that a CIA task force has been soft-pedaling its investigation into a mysterious illness impacting agency officers and diplomats known colloquially as “Havana Syndrome,” sources tell CNN.But about two dozen cases remain unexplained, which the government vaguely refers to as “anomalous health incidents.” “There’s just no answer,” said one House Intelligence Committee member briefed on the CIA task force’s work.None.” Among the complaints lodged by CIA officers over the past year is that the agency task force isn’t doing enough to run down legitimate leads that might expose who or what is causing these strange episodes.To me, this is where they need to be held accountable to explain why.” CIA officials dispute the notion that the task force isn’t conducting a rigorous and thorough investigation, with one agency official calling it “among the most full-scale and aggressive approaches to an investigation that CIA and other agencies have taken.” CIA director William Burns in a statement to CNN also said the agency is fulfilling its “profound obligation” to conduct “the most rigorous investigation possible.” “We have assembled a large team of some of our very best officers who are focused exclusively on this issue, and we are following every single lead,” Burns said.One so-called experts panel – made up of scientific, medical, and engineering specialists who have access to classified information about the incidents – has examined possible mechanisms behind the episodes and is expected to deliver a classified report on its findings to Congress in the coming weeks, according to two sources familiar with the matter."