WASHINGTON — The C.I.A. has found that most cases of the mysterious ailments known as Havana syndrome are unlikely to have been caused by Russia or another foreign adversary, agency officials said, a conclusion that angered victims.
A majority of the 1,000 cases reported to the government can be explained by environmental causes, undiagnosed medical conditions or stress, rather than a sustained global campaign by a foreign power, C.I.A. officials said, describing the interim findings of a comprehensive study.
