The Cuban Foreign Ministry said on Wednesday it had started an "exhaustive" investigation into the freakish incidents which the United States said had caused physical symptoms in its diplomats serving here.
The State Department says it is too early to determine who or what is responsible for a string of health issues that prompted some USA diplomats and their families to leave Cuba. The Associated Press reports that American officials have concluded that the diplomats in Havana were exposed to an advanced device that operated outside the range of audible sound.
Nauert said the State Department first heard about the incidents in "late 2016". The State Department is taking these incidents "very seriously", she added, and is working to determine the cause and impact of the incidents.
The State Department asked the Cubans to leave their embassy in the USA on May 23, but CBS first reported the information this week.
Nauert said the affected staff received medical examinations and are being monitored as officials continue to investigate the cause.
"What this requires is providing medical examinations to these people", Nauert said. A spokesperson for the Canadian government said that authorities, "are aware of unusual symptoms affecting Canadian and USA diplomatic personnel and their families in Havana".
Officials said it was unclear whether the incident was a deliberate attack, and added that other states such as Russian Federation were being investigated for acts that the Cuban government may have been unaware of. The Obama administration also approved a package of regulatory changes that was meant to expand scientific, humanitarian, trade and commercial opportunities between the USA and Cuba. "I can't tell you the exact number ... but we had to bring some Americans home or some Americans chose to come home as a result of that".
The Cuban Government said that it has never allowed the island to be used for actions against diplomats and was willing to cooperate to clarify the facts.
William LeoGrande, a specialist in Cuban politics and US foreign policy toward Latin America at American University School of Public Affairs in Washington, said it made no sense for the Cubans to do this deliberately, but also dismissed the idea of Russian involvement. Like virtually all foreign diplomats in Cuba, the victims of the incidents lived in housing owned and maintained by the Cuban government.
They also will ask why Josefina Vidal Ferreiro, Cuba's ambassador to Canada who served as the public face of normalization talks with the United States and previously served as the Castro regime's head of North American affairs, was in Moscow at the end of July.
USA diplomats in Cuba said they suffered occasional harassment for years after the restoration of limited ties with the communist government in the 1970s, harassment reciprocated by US agents against Cuban diplomats in Washington.
According to a statement released Wednesday by the Cuban government, the foreign ministry was made aware of the incidents on February 17 and promptly launched an investigation into the matter. One US diplomat now will need to use a hearing aid as a result of the injuries they suffered, according to the source.
Several of the diplomats were recent arrivals at the embassy, which reopened in 2015 as part of former President Barack Obama's reestablishment of diplomatic relations with Cuba.