WASHINGTON — The State Department is expected to announce Friday that it will pull much of its staff out of the American embassy in Havana, Cuba, in the wake of mysterious attacks that have injured 21 people associated with the embassy.
The announcement, first reported by CBS News, will come just three days after Secretary of State Rex W. Tillerson met with Bruno Eduardo Rodríguez Parrilla, Cuba’s foreign minister, in Washington. That meeting failed to persuade Mr. Tillerson that the Cubans could guarantee the safety of the remaining American employees in Havana, prompting him to decide to pull much of the embassy staff, an American official said.
The American Foreign Service Association reported this month that the symptoms among those affected included mild traumatic brain injury, permanent hearing loss, loss of balance, severe headaches and brain swelling.
Mr. Tillerson had been considering closing the embassy, which had only recently reopened after decades of frosty relations between the two countries. But one of the reasons Mr. Tillerson will keep it open is a growing belief among American officials that the Cuban government was probably not responsible for the attacks.
A former senior American official said there was information that the Cubans were rattled by what had happened and were desperate to figure it out the cause. A third country may have been responsible, the official said.
The official said that the F.B.I. had visited the homes of diplomats in Cuba and had not been able to detect anything. The F.B.I. has also reviewed security footage of the homes and found nothing suspicious. The F.B.I. has been unable to duplicate the effects the diplomats have experienced in a lab.
Heather Nauert, the State Department’s spokeswoman, said that Mr. Tillerson and Mr. Rodríguez Parrilla had had a “conversation that was firm and frank and reflected the United States’ profound concern for the safety and security of its diplomatic personnel.”
That the Cubans offered to let the F.B.I. go to Havana and investigate represented a rare level of openness and was seen as yet another indicator that the Cubans themselves have been shaken by the incident.
American officials have speculated that the problems may have resulted from some sort of sonic attack or perhaps a surveillance operation gone wrong. The attack may have been the work of a country like Russia or rogue government unit. The fact that a Canadian diplomat was also affected has deepened the mystery. Relations between Canada and Cuba have long been warm.
The Trump administration has already reversed crucial pieces of what President Trump has called a “terrible and misguided deal” with Cuba that was struck during the Obama administration by reinstating travel and commercial restrictions on Cuba. But the administration seems to have little appetite for entirely undoing other measures that are broadly popular, including among Republicans.
But Mr. Tillerson has long said that the safety of American diplomats is his top priority, and he is known to start every meeting of his senior staff by asking whether everyone is safe. However, nearly nine months into his tenure, Mr. Tillerson has yet to get someone nominated to lead the Bureau of Diplomatic Security, part of the State Department charged with safeguarding American diplomats around the world.