WASHINGTON (Reuters) - The United States is considering closing its embassy in Havana in response to an alleged sonic attack on U.S. personnel in Cuba, Secretary of State Rex Tillerson said on Sunday. 
 
 “We have it under evaluation,” Tillerson said on CBS’ “Face the Nation” program. “It’s a very serious issue with respect to the harm that certain individuals have suffered.” 
 
 Five Republican senators on Friday called for the Trump administration to retaliate against the Cuban government by expelling Cuban diplomats and possibly shuttering the U.S. embassy there over attacks that began in late 2016. 
 
 The State Department said in August that Americans linked to the U.S. embassy in Havana had experienced physical symptoms from “incidents” involving sound waves. Five Canadians were also affected. 
 
 Symptoms included nausea, dizziness and temporary loss of hearing or memory. 
 
 Cuba, the United States and Canada have investigated the attacks, but the probe has not yielded any answers about how they were carried out or who was responsible for them. 
 
 Cuba has denied involvement. The U.S. State Department has not blamed Havana for the attacks but asked two Cuban diplomats to leave Washington in May. 

 SHARE THIS ARTICLE Share Tweet Post Email 
 
 Photographer: Dado Galdieri/Bloomberg Photographer: Dado Galdieri/Bloomberg 
 
 New York (AP) -- The Trump administration is considering closing down the recently reopened U.S. Embassy in Havana following a string of unexplained incidents harming the health of American diplomats in Cuba, Secretary of State Rex Tillerson said Sunday. 
 
 Tillerson's comments were the strongest indication to date that the United States might mount a major diplomatic response, potentially jeopardizing the historic restart of relations between the U.S. and Cuba. The two former foes reopened embassies in Washington and Havana in 2015 after a half-century of estrangement. 
 
 "We have it under evaluation," Tillerson said of a possible embassy closure. "It's a very serious issue with respect to the harm that certain individuals have suffered. We've brought some of those people home. It's under review." 
 
 Of the 21 medically confirmed U.S. victims — diplomats and their families — some have permanent hearing loss or concussions, while others suffered nausea, headaches and ear-ringing. Some are struggling with concentration or common word recall, The Associated Press has reported . 
 
 Some victims felt vibrations or heard loud sounds mysteriously audible in only parts of rooms, leading investigators to consider a potential "sonic attack." Others heard nothing but later developed symptoms. 
 
 Tillerson once called the events "health attacks," but the State Department has since used the term "incidents" while emphasizing the U.S. still doesn't know what has occurred. Cuba has denied any involvement or responsibility but stressed it's eager to help the U.S. resolve the matter. 
 
 The U.S. has said the tally of Americans affected could grow as more cases are potentially detected. 
 
 The last reported incident was on Aug. 21, according to a U.S. official briefed on the matter. The official wasn't authorized to discuss the matter publicly and requested anonymity. 
 
 A decision to shutter the embassy, even temporarily, would deal a demoralizing blow to the delicate detente that President Barack Obama and Cuban leader Raul Castro announced in late 
 
 2014. The next year, embassies were reopened and restrictions on travel and commerce eased — signs of a warming relationship that displeased some hard-liners in Cuba's government. President Donald Trump has reversed some of the changes, but left many in place. 
 
 Tillerson spoke on CBS' "Face the Nation" as world leaders and top diplomats descended on New York for annual U.N. General Assembly meetings. President Donald Trump will give his first speech on the major global platform this week. 
 
 Cuba is also represented at the U.N., but it's not expected Trump will meet with any Cuban leaders or officials during his visit. 
 
 The U.S. hasn't identified either a culprit or a device. Investigators have explored the possibility of sonic waves, an electromagnetic weapon, or an advanced spying operation gone awry, U.S. officials briefed on the probe told the AP. The U.S. hasn't ruled out that a third country or a rogue faction of Cuba's security services might be involved. 
 
 In Washington, lawmakers in Congress have been raising alarm over the incidents, with some calling for the embassy to be closed. On Friday, five Republican senators wrote Tillerson urging him to not only shutter the embassy, but also kick all Cuban diplomats out of the United States — a move with dramatic diplomatic implications 
 
 "Cuba's neglect of its duty to protect our diplomats and their families cannot go unchallenged," said the lawmakers, who included Sen. Tom Cotton of Arkansas, who led the effort, and Sen. Marco Rubio of Florida, a prominent Cuban-American and critic of the U.S. detente. 
 
 The incidents have frightened Havana's tight-knit diplomatic community, raising concerns about the potential scope. At least one other country, France, has tested embassy staff for potential sonic-induced injuries, the AP has reported. 
 
 ___ 
 
 Reach Josh Lederman on Twitter at http://twitter.com/joshledermanAP 

 Secretary of State Rex Tillerson said Sunday that the United States is considering closing the U.S. Embassy in Havana in response to mysterious hearing problems that have left at least 21 employees with serious health issues. 
 
 "We have it under evaluation," Tillerson said on CBS's "Face the Nation" when asked about calls by some senators to shutter the diplomatic mission. "It's a very serious issue, with respect to the harm that certain individuals have suffered, and we've brought some of those people home. It's under review." 
 
 Closing the embassy would be a serious setback to relations between the United States and Cuba, two Cold War adversaries whose enmity stretched more than half a century before they restored diplomatic relations and upgraded their missions into embassies in 2015. 
 
 But at least 21 Americans who worked in the U.S. Embassy in Cuba have reported medical problems since late last year, when percussive attacks on their residences began. The incidents apparently continued into 2017. Two Cuban diplomats have been expelled from the embassy in Washington in response. 
 
 The State Department did not talk publicly about the incident until August, months after the problems were uncovered. 
 
 [Trump’s Cuba policy tries to redefine ‘good’ U.S. tourism.] 
 
 
 
 The FBI is investigating what the union representing Foreign Service officers calls “sonic harassment attacks” on the diplomats at the U.S. Embassy in Havana. (Desmond Boylan/AP) 
 
 Some of the victims suffered mild traumatic brain injuries, hearing loss and other neurological and physical ailments, said the union representing Foreign Service officers. The FBI is investigating what the union calls "sonic harassment attacks" on the diplomats. A Canadian diplomat also reported similar problems. 
 
 Cuba has denied any responsibility for the attacks. 
 
 Cuban President Raúl Castro called in the then-head of the U.S. mission, Jeffrey DeLaurentis, to express concern. 
 
 Five Republican senators wrote Tillerson last week asking him to close the embassy and expel Cuba's diplomats from the United States. 
 
 "We ask that you immediately declare all accredited Cuban diplomats in the United States persona non grata and, if Cuba does not take tangible action, close the U.S. Embassy in Havana," the senators wrote. "Cuba's neglect of its duty to protect our diplomats and their families cannot go unchallenged."
– No one knows what's injuring US diplomats in Havana, not even (ostensibly) Raul Castro. And so Rex Tillerson said on Sunday's Face the Nation that the US government is considering closing the US Embassy there in response to this "serious issue," per the AP. "We have it under evaluation," the secretary of state noted. There have been 21 US diplomats and relatives with confirmed health issues so far, including concussions, hearing loss, and headaches, and the US says more cases may emerge as the probe continues. Those affected have reported feeling vibrations or hearing sounds before their symptoms began, while others didn't notice anything at all initially. The AP notes closing the embassy would be a "devastating blow" to the "warming relationship" between the US and Cuba, jump-started in 2014 by then-President Obama and Castro after a 50-year deep freeze. Reuters reports the US, Cuba, and Canada have all been trying to figure out exactly what the "incidents," as the US State Department calls them, are (Tillerson himself has used the term "health attacks") and who's behind them, but to no avail. Cuba has denied involvement and said it, too, wants answers. Other perpetrator possibilities the US is considering: a different state entity or members of Cuba's security forces acting on their own. Besides asking for the embassy to be shut down, some US lawmakers, including Sens. Tom Cotton and Marco Rubio, want further repercussions, such as booting Cuban diplomats from the US completely; the Washington Post notes two Cuban diplomats have already been kicked out of the embassy in DC. "Cuba's neglect of its duty to protect our diplomats and their families cannot go unchallenged," Cotton said in a Friday letter to Tillerson from five GOP senators.