Mysterious symptoms of the so-called Havana syndrome have been linked to a Russian intelligence unit. Moscow says the report's conclusions are "unfounded" The condition has affected American diplomats in recent years, who have reported unexplained symptoms.
Russia's unit 29155 conducts operations abroad and has been blamed for several international incidents, including the attempted poisoning of defector Sergei Skripal in Britain in 2018. Washington closed its immigration office in Havana in 2018 due to a change in US policy towards Cuba and due to the fear that the syndrome generated among diplomats.