"Acoustic attack" reported U.S. diplomats in Cuba, consisted of the sounds of more than 20 frequencies. On it informs Agency Associated Press, which received the corresponding audio recording.

Journalists described the sounds as "high frequency sound of crickets combined with scratching nails down a chalkboard". The Agency said that the record was sent for analysis in the laboratory of the Navy of the United States, but experts failed to understand how she is hurting diplomats.

The incident happened in August, when 22 employees of the American Embassy in Cuba, heard the sound, asked for medical help. After this, most of the Embassy employees were evacuated, and the President of the United States Donald trump went to the aggravation of relations with Havana, deported from the USA 15 Cuban diplomats.

According to U.S. media, we are talking about the "acoustic attack", which led the victims to long-term hearing loss. According to CNN, it was just a series of connected episodes.

Working in Cuba and injured Americans and Canadians have experienced nausea, headaches, equilibrium disturbances, and symptoms similar to those which happen in the brain damage and Central nervous system. Some of the injured were taken to hospitals in Miami, the other in Havana went American doctors. Havana has promised us authorities to help investigate this situation.

In June, Donald trump announced a partial abandonment of the policy of his predecessor Barack Obama against Cuba. It introduces more stringent restrictions on American travel to Cuba tourism and a ban on business transactions of persons subject to U.S. jurisdiction with the Cuban military agencies.

The administration, trump said that the effect of the existing sanctions against Cuba would be extended, and any improvement in this area is possible only under the condition that Havana will take steps aimed at political and economic liberalization.

In 2014, the head of the United States and Cuba, Barack Obama and Raul Castro announced the beginning of a gradual normalization of relations between the two countries. Was restored diplomatic ties, resumed regular commercial flights, weakened a number of anti-Cuban sanctions. Imposed by U.S. authorities after the revolution of 1959 trade embargo is still in effect.

USA in 1960 has imposed on the island nation of the trade embargo. Washington took this step after in 1959 as a result of the revolution to power in Cuba came the rebels led by Fidel Castro.