At least 21 embassy staff and family members reported a range of health problems including deafness, dizziness and nausea to mild brain trauma. Earlier reports said Washington made the order after diplomats were targeted by sonic attacks, which use sonic and ultrasonic weapons to injure, incapacity or kill an opponent. Citizens were urged not to travel to Havana because some of the attacks took place at hotels were Americans stay, according to a senior State Department official. American officials said the US embassy will lose around 60 per cent of its staff, and will stop processing visas there indefinitely.

A US state department official said: “Until the government of Cuba can ensure safety of our people, we will be reduced to emergency personnel so as to minimise the number of US government personnel at risk of exposure. "At least 21 employees have been targeted in specific attacks.” He said non-essential embassy staff would be withdrawn as well as all family members.

The Cuban government has denied any role and is investigating the incident. Despite an investigation by the FBI, Cuban authorities and the Royal Canadian Mounted Police, officials have been unable to determine the cause of the attacks, which date back to late 2016. But the senior State Department official stressed "the government of Cuba is responsible for taking all appropriate steps to prevent attacks on our diplomatic personnel in Cuba”. The official said: “We don’t know the means, the methods or how the attacks are being carried out.” The partial evacuation is set to deliver another blow to former US President Barack Obama's policies of engagement with Cold War foe Cuba. Although Washington has not cast direct blame on Cuban authorities, Secretary of State Rex Tillerson reminded Cuban Foreign Minister Bruno Rodriguez that it was Cuba's obligation to protect diplomats and their families during a meeting in Washington on Tuesday. The symptoms of the 21 US embassy personnel harmed included "hearing loss, dizziness, tinnitus, balance problems, visual complaints, headache, fatigue, cognitive issues and difficulty sleeping”. Denis Bedat, a specialist in bio-electromagnetics, earlier this week said staff in Havana could have been targeted by audio-waves, which left them with chronic hearing issues. Mr Bedat said using an inaudible sound device for a sonic attack is “quite plausible from technical point of view”. He added: “Ultrasonic waves, beyond the acoustic capacity of humans, can be broadcast with an amplifier and the device does not need to be large, or used inside or outside the house.” The senior State Department official added: "Because our personnel's safety is at risk and we are unable to identify the source of the attack, we believe that U.S. citizens may also be at risk and warn them not to travel to Cuba.” </s> At least 16 Americans in Cuba have experienced symptoms as a result of the acoustic attacks on diplomats, State Department spokeswoman Heather Nauert said in the first public confirmation of the number of people affected.

Nauert was unsure if that figure included family members. On Wednesday, CBS News exclusively reviewed medical records showing mild traumatic brain injuries and possible damage to the central nervous system as a result of the attacks. The symptoms have forced some workers to return to the U.S., while others have remained in Havana.

The State Department said no devices were found, according to their determination from talking to staff and medical professionals. The State Department claims the attacks are not "ongoing," and has called the incidents "unprecedented."

Cuba has denied any responsibility in the attacks, while the U.S. has maintained it is Cuba's responsibility to protect foreign diplomats.

Diplomats complained about symptoms ranging from hearing loss and nausea to headaches and balance issues after the State Department said "incidents" began affecting them in late 2016. A source familiar with the incidents told CBS News officials are investigating whether the diplomats were targets. The attacks were directed at their homes, which the Cuban government provides. </s> WASHINGTON — At least 16 U.S. government employees or their family members in Cuba have experienced symptoms, including hearing damage, that have required medical attention, the State Department confirmed Thursday.

"We take this situation very seriously," State Department Spokesperson Heather Nauert said Thursday. "We are trying to provide them the help, the medical help, the medical care and treatment that they need and the support that they deserve."

This was the first time the agency has spoken publicly about the number of those affected by the what officials are describing as "incidents" that began late last year.

What caused the health symptoms for the 16 Americans is still unknown. U.S. intelligence officials say a range of possibilities is being considered, based on the reported symptoms, and it’s not clear whether ultrasonic sound waves were to blame. It could also have been radio waves or even attempted poisoning, one official has said.

"This is unprecedented," Nauert had said Wednesday. "We have not seen this type of activity take place before."

A multi-agency U.S. investigation is ongoing and as of Thursday the U.S. is still not assigning blame. State Department Diplomatic Security, which is responsible for the security of American personnel, U.S. intelligence agencies and other government agencies with expertise about potential causes are all involved.

A senior State Department official said the Cuban government has been responsive.

Cuban officials have denied directing any actions against the U.S. government employees and have launched their own investigation into the incidents. The U.S. has left open the possibility of a third country's involvement.

A senior State Department official confirmed that the "incidents" stopped this spring although some people may still be experiencing symptoms which have manifested differently in different individuals.

Nauert said Thursday the U.S. has determined the incidents had ceased through conversations with the affected employees and medical personnel but nothing, such as a piece of equipment, has yet been identified as the source or the cause.

Publicly, the State Department has said only that the Americans returned home with "physical issues." One State Department official confirmed reports that the diplomats were experiencing symptoms of hearing loss, and a Cuban government official told NBC News the Americans had complained of an acoustic "incident."

Some of the U.S. government employees were medically evacuated to Miami, Florida, to receive medical treatment and testing. For others who chose to stay in Cuba, medical professionals were brought to that country to treat and test those affected.

A senior State Department Official said the department was in close contact with the U.S. employees in Havana and described many meetings where the charge d’affaires heading the embassy gathered staff to compare notes.

"These are US government employees that we're talking about," Nauert said Wednesday. "What has happened there is of great concern to the US government, the State Department, the White House, other agencies and departments involved as well." </s> WASHINGTON (Reuters) - Mysterious “incidents” caused physical symptoms in at least 16 Americans linked to the U.S. embassy in Cuba, the State Department said on Thursday, in what media reports have described as an “acoustic attack.”

FILE PHOTO: An exterior view of the U.S. Embassy is seen in Havana, Cuba, June 19, 2017. REUTERS/Alexandre Meneghini

The State Department earlier this month said Americans serving at the U.S. embassy in Havana had experienced physical symptoms caused by unspecified “incidents” starting as far back as late 2016.

A U.S. government official said in August that several colleagues at the U.S. embassy in Havana were evacuated back to the United States for hearing problems and other symptoms. Some subsequently got hearing aids, said the official, who spoke on condition of anonymity.

State Department spokeswoman Heather Nauert said on Thursday that 16 or more U.S. government employees and family members based in Cuba had experienced symptoms of some sort, a number that was previously not known.

“We can confirm that at least 16 ... members of our embassy community have experienced some kinds of symptoms,” Nauert said.

Those affected received medical care in the United States and Cuba, and some of those who experienced symptoms have decided to remain in Havana, Nauert said.

CBS reported this week that Americans and Canadians working in Cuba had been diagnosed with hearing loss, nausea, headaches and balance disorders and conditions as serious as mild traumatic brain injury and damage to the central nervous system.

Citing a source familiar with the incidents, CBS said officials are investigating whether the diplomats were targets of some form of sonic attack directed at their homes.

“The incidents are no longer occurring,” Nauert said.

Cuba has denied involvement in the incidents, and said this month that it is investigating the U.S. allegations. The State Department has not blamed Cuba for the attacks, but did ask two Cuban diplomats to leave Washington in May. </s> Echoes Of Cuba? U.S. Employee In China Hit With 'Sensations Of Sound And Pressure'

The State Department said that a U.S. government employee assigned to Guangzhou, China, has reported experiencing "vague, but abnormal, sensations of sound and pressure."

Secretary of State Mike Pompeo said on Wednesday that "the medical indications are very similar and entirely consistent" with the symptoms reported by Americans working at the U.S. Embassy in Cuba. "We have medical teams that are moving to be on the ground there. We are working to figure out what took place both in Havana, and now in China, as well."

The federal employee reported experiencing physical symptoms from late 2017 through April 2018, when he or she returned to the U.S. for medical evaluation. That evaluation found that the employee's symptoms were similar to those of someone with a head concussion or mild traumatic brain injury.

The U.S. operates a consulate in Guangzhou, a sprawling commercial city and port in southern China. The Chinese government has assured the U.S. that it is investigating the matter and taking appropriate measures, according to a State Department spokesperson.

Suspected "sonic attacks" affecting more than a dozen U.S. diplomats and family members in Havana beginning in November 2016 led to the U.S. pulling all nonessential staff from the embassy and expelling 15 Cuban diplomats last year. Cuba has denied any involvement in the attacks.

Though some experts expressed doubt when the possibility of a sonic attack in Cuba was first raised, the State Department points to a study by independent medical personnel published earlier this year in The Journal of the American Medical Association.

That study found that 21 U.S. government employees in Havana experienced "persistent cognitive, vestibular, and oculomotor dysfunction, as well as sleep impairment and headaches, were observed ... associated with reports of directional audible and/or sensory phenomena of unclear origin. These individuals appeared to have sustained injury to widespread brain networks without an associated history of head trauma."

Dr. Charles Rosenfarb, the State Department's medical director, told a Senate subcommittee in January that the employees "associated the onset of these symptoms to their exposures with unusual sounds or auditory sensations. Various descriptions were given: 'a high-pitched beam of sound'; an 'incapacitating sound'; a 'baffling sensation' akin to driving with the windows partially open in a car; or just an intense pressure in one ear."

The State Department says it doesn't know what caused the reported symptoms in Guangzhou, and isn't aware of any other similar cases in China.

But it did issue a warning Wednesday: "While in China, if you experience any unusual acute auditory or sensory phenomena accompanied by unusual sounds or piercing noises, do not attempt to locate their source. Instead, move to a location where the sounds are not present."

The U.S. government has about 2,000 employees posted to China. The mysterious incident comes at a time of tension between the U.S. and China over trade disputes. </s> A young woman talks on her mobile phone as she walks past a mural depicting (L-R) Cuban Comunist Party founder Julio Antonio Mella and Cuban revolutionary leaders Camilo Cienfuegos and Che Guevara in the Habana Vieja neighborhood January 24, 2015 in Havana, Cuba. Diplomats from the United States and Cuba held historic talks this week that could restore diplomatic ties and mark the end of more than 50 years of of Cold War-era hostility between the two countries. Chip Somodevilla/Getty Images
• Mysterious "sonic weapons" have been blamed for symptoms affecting American and Canadian diplomats in Cuba.
• Sound-based weapons exist, but experts aren't sure whether any were actually used in this case.

More than 10 US diplomats and their family members in Cuba have experienced strange symptoms including hearing loss, mild traumatic brain injury, and central nervous system damage after being exposed to some kind of mysterious sonic weapon, according to a review of medical records by CBS News.

The Associated Press reported: "After months of investigation, U.S. officials concluded that the diplomats had been exposed to an advanced device that operated outside the range of audible sound and had been deployed either inside or outside their residences. It was not immediately clear if the device was a weapon used in a deliberate attack, or had some other purpose."

But a number of experts aren't sure whether such a device exists.

"There isn't an acoustic phenomenon in the world that would cause those type of symptoms," Seth Horowitz, a neuroscientist and author of the book "The Universal Sense: How Hearing Shapes the Mind," told Business Insider via email.

Horowitz explained that no known inaudible — and seemingly undetectable — device could have the properties attributed to these strange sonic weapons.

Would someone target diplomats with mysterious devices?

Starting in late 2016, a number of diplomats and their family members sought medical attention for mysterious nausea, hearing problems, and balance issues. At least five Canadians have experienced similar symptoms, according to CNN.

The attacks — if that's what they were — appear to have stopped. But it remains unknown what sort of device could have caused these medical issues and who was behind these attacks.

FILE PHOTO: An exterior view of the U.S. Embassy is seen in Havana, Cuba Thomson Reuters

Diplomats have experienced other forms of harassment, like break-ins and surveillance, since the US formally restored diplomatic relations with Cuba in 2015. But a physical attack is unprecedented, and many experts say Cuba has no interest in damaging relations with the US. Some experts have said that the fact Canadians experienced similar symptoms make the possibility of an intentional "attack" even less likely, since Cuba and Canada have a strong relationship.

Because of these factors, experts wonder whether the symptoms could be the result of a third party (potentially from another government) trying to sabotage US-Cuban relations. Others have mused that this could be some sort of eavesdropping device gone haywire.

It "sounds like a science experiment," James Carson, former head of the US Interests Section in Havana, told The New York Times.

For the most part, it seems victims didn't hear anything, which implies the device operates outside the audible range of sound. But CNN's report said two officials also described "a deafeningly loud sound similar to the buzzing created by insects or metal scraping across a floor," though no one knew where that sound came from.

Toby Heys, the leader of Manchester Metropolitan University's Future Technology research center told New Scientist that it's possible for something emitting infrasound — vibrations at a frequency below what humans can hear — to cause hearing loss. But Heys said that would require large subwoofers, making covert deployment unlikely.

Ultrasound devices, which operate above the range of human hearing, exist and could damage the ears, Heys said. But these would need to be directly targeted into the ear.

"Overall, I would be pretty circumspect about the claims to be honest — it is all very Philip K. Dick territory," Heys said. "That said, we are living in a fairly surreal world right now."

Horowitz said via email that without more evidence of these weapons, this incident should be considered a non-story, and that other possible explanations for these medical problems should be considered.

Sonic weapons have been used to repel Somali pirates. AP

The use of sonic weaponry

Sonic weapons do exist, but for the most part they are "highly visible and easy to avoid," according to Horowitz.

Such weapons include long range acoustic devices, or LRADs, which emit a shill, loud, disabling sound that can damage the hearing of people more than 900 feet away. These devices have been used by US troops in Iraq, for crowd control in New Orleans after Hurricane Katrina, and by cruise ships to repel Somali pirates. Similar "sound cannons" were also used by police against protestors at the G-20 meetings in Pittsburgh in 2009.

But those devices are large and emit obvious sounds. A mystery machine that emits harmful, silent waves defies any immediate explanation.

Business Insider has reached out to other experts on non-lethal weaponry and will update this post if a plausible explanation emerges. </s> WASHINGTON, May 23 (Reuters) - U.S. Secretary of State Mike Pompeo said on Wednesday that an incident reported in Guangzhou, China, had similarities to a case in Cuba last year where U.S. diplomats became ill amid accusations that they had been victims of a sonic attack.

"The medical indications are very similar, and entirely consistent with, the medical indications that have taken place to Americans working in Cuba," Pompeo said during testimony in the U.S. Congress.

"We have medical teams that are moving to be on the ground there. We are working to figure out what took place both in Havana and in, now in China as well," he told the House of Representatives Foreign Affairs Committee.

Washington last year expelled two Cuban diplomats over the alleged incidents in Havana, which it said caused symptoms from hearing loss to nausea in U.S. embassy staff and their families. (Reporting by Patricia Zengerle Editing by Chizu Nomiyama and Tom Brown) </s> A number of U.S. personnel in China have been sent back to the U.S. for further tests after health screenings found symptoms similar to the mysterious "acoustic" illness experienced by some U..S. staffers in Cuba, according to the U.S. State Department.

The medical teams were sent to the southern Chinese city of Guangzhou after an employee had complained of “subtle and vague, but abnormal sensations of sound and pressure” over several months from late 2017 until April.

"As a result of the screening process so far, the Department has sent a number of individuals for further evaluation and a comprehensive assessment of their symptoms and findings in the United States," State Department spokeswoman Heather Nauert said Wednesday.

She said the tests were offered to “any personnel who have noted concerning symptoms or wanted baseline screening.”

Last month, Secretary of State Mike Pompeo said a U.S. government employee stationed in Guangzhou had reported "abnormal sensations of sound and pressure" suggesting a mild brain injury. Pompeo said the medical indications are "very similar" and "entirely consistent" to those reported by American diplomats posted in Havana.

In 2016, some U.S. government personnel in Cuba reported hearing weird, loud sounds along with feelings of changes in air pressure in their homes owned and maintained by the Cuban government as well as hotel rooms. Although there had been no history of head trauma, the symptoms reported were consistent with brain injury.

The diplomats described the sounds as “buzzing, grinding metal, piercing squeals and humming.”

In response, the State Department initially reduced the number of workers in Havana, but in March made the sharp reductions permanent, citing health concerns. Some 15 Cuban embassy employees were ordered to leave the United States, although Washington has not formally charged Cuba with any deliberate attacks over the health issues.

Cuba has said there were no attacks and strongly denied any allegations of wrongdoing.

Asked about the latest incidents in Guangzhou, Chinese Foreign Ministry spokeswoman Hua Chunying said the U.S. had not formally raised the matter with Beijing.

“If the U.S. makes formal contact with us, China will continue necessary investigations in an earnest and responsible manner and maintain close communication and cooperation with the U.S.,” Hua said at a news conference.

The diplomats in Cuba described the sounds as “buzzing, grinding metal, piercing squeals and humming.”

An expert panel set up by the State Department last year said the initial findings were most likely related to "neurotrauma from a non-natural source" and recommended further investigation.

The New York Timesidentified the latest American employee evacuated from China as Mark A. Lenzi, a security engineering officer who left Wednesday night with his wife and two children.

Lenzi told the Times he lived in the same apartment tower as the officer evacuated in April and suffered in recent months from what he called “neurological symptoms.”

A U.S. official, who wasn’t authorized to discuss the situation publicly and requested anonymity, told the Associated Press that the evacuees from China were being tested at the University of Pennsylvania, where patients from Cuba were also treated and evaluated.

The Penn team has said the patients experienced persistent disability though rehabilitation therapy customized for them seemed to help.

In April, Canada also ordered families of diplomatic staff in Cuba to return home after mysterious health symptoms were detected in 10 Canadians stationed on the island.

Canada said the 10 continued to show unexplained brain symptoms and that “medical information raised concerns for a new type of a possible acquired brain injury.” Symptoms included dizziness, headaches and an inability to concentrate. </s> The State Department announced Thursday that more than a dozen Americans connected to the U.S. Embassy in Havana, Cuba, have been affected by mysterious health incidents.

Heather Nauert, a spokeswoman for the agency, confirmed to reporters at a press briefing that 16 U.S. diplomats have experienced symptoms related to what the State Department has described as “attacks.”

“We can confirm that at least 16 U.S. government employees, members of our embassy community, have experienced some kind of symptoms,” Nauert said. “They have been provided medical treatment in the United States, as well as in Cuba.”

The incidents began in late 2016 when embassy staff began to complain of numerous health issues including hearing loss, headaches and nausea.

The Associated Press reported earlier this month that an investigation by U.S. officials linked the symptoms to “a covert sonic device.”

“U.S. officials concluded that the diplomats had been exposed to an advanced device that operated outside the range of audible sound and had been deployed either inside or outside their residences,” the AP wrote. “It was not immediately clear if the device was a weapon used in a deliberate attack, or had some other purpose.”

The State Department retaliated in late May by expelling two Cuban diplomats from their embassy in Washington D.C. – a move condemned by Cuba at the time as “unjustified and baseless.”

“Cuba has never permitted, nor will permit, that Cuban territory be used for any action against accredited diplomatic officials or their families, with no exception,” the Cuban government said in early August.

Medical records reviewed by CBS News Wednesday revealed that the U.S. diplomats were diagnosed with conditions as serious as “mild traumatic brain injury” with “likely damage to the central nervous system.”

While the episode has been described as “unprecedented” by the State Department, some experts remain skeptical regarding the use of sonic weapons.

John Sipher, a 28-year veteran of the Central Intelligence Agency’s National Clandestine Service, speculated Monday that the incident may have been a “surveillance effort gone wrong.”

“We have very little experience anywhere in the world with directed attacks designed to physically harm our diplomats,” Sipher wrote at Just Security. “However, the use of intrusive technical collection and surveillance which sometimes causes harm in its own right, is consistent with past practice in Cuba and elsewhere.”

Sipher added that such an attack, at least from the Cuban government, would be an unlikely event given the timing.

“If the operations began shortly after the US presidential elections, it would have been irrational for Cuba to start out relations with the incoming administration in this manner,” Sipher wrote. “Further, I suspect if the Trump Administration believed Cuba sought to purposely harm U.S. diplomats, they would have reacted in a more aggressive and public manner.”

U.S. investigators are also looking into the possibility that an outside country, such as Russia – concerned over the growing relationship between the U.S. and its longtime ally – carried out the suspected operation without the knowledge of Cuba.
The United States State Department says at least 16 U.S. government employees and family members based in Cuba showed physical symptoms from the previously reported acoustic attacks. Investigators are exploring whether some form of sonic attack was directed at diplomats' homes.