A US government employee in China suffered brain trauma linked to "abnormal sounds" that resembled the still-unexplained injuries that befell US and Canadian diplomats in Cuba last year, Secretary of State Mike Pompeo said Wednesday.
US and Chinese authorities are investigating after the unnamed American citizen, who was assigned to the southern city of Guangzhou, was diagnosed with mild traumatic brain injury (MTBI).
The US embassy in Beijing issued a health alert Wednesday over the incident, while saying it does not know what caused the symptoms or of any similar situations in the country.
Last year 24 US diplomats and their family members in Cuba fell victim to mysterious "attacks" that left them with injuries resembling brain trauma. Ten Canadian diplomats and their relatives also suffered a strange illness.
Both countries scaled back their presence on the Caribbean island due to the problem, which continues to baffle investigators and has strained US diplomatic relations with Havana.
"The medical indications are very similar and entirely consistent with the medical indications that have taken place to Americans working in Cuba," Pompeo said in Washington.
"We are working to figure out what took place both in Havana and now in China as well," he said.
- Embassy warning -
Jinnie Lee, a spokeswoman for the US embassy in Beijing, said the US citizen experienced a variety of physical symptoms between late 2017 and April 2018. The person was sent to the United States and diagnosed with MTBI on May 18.
The embassy's health alert says the employee "recently reported subtle and vague, but abnormal, sensations of sound and pressure."
"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 embassy said.
In Washington for talks with Pompeo, Chinese Foreign Minister Wang Yi said the US should avoid politicizing the case.
"We don't want to see that this individual case would be magnified, complicated or even politicized," Wang told reporters.
"China has been investigating this matter in a very responsible manner."
"We haven't found that any organization or individual has carried out such a sonic influence," Wang added, suggesting the US carry out an "internal" probe into the case.
- Cuban case -
In Cuba, the American victims had associated the onset of their symptoms with "unusual sounds or auditory sensations," a State Department physician told the US Senate in January.
Charles Rosenfarb, a doctor and director of the State Department bureau of medical services, said the symptoms were mixed but consistent with brain trauma.
The victims suffered headaches, hearing loss, disorientation and some loss of cognitive ability.
Initially officials suspected the Americans had been targeted by some sort of acoustic weapon. But so far, no evidence has been made public to support that theory, and Pompeo did not suggest the State Department understood the cause yet.
The incident prompted the United States to withdraw more than half of its personnel from the embassy in Havana, just two years after it had reopened as part of a restoration of full diplomatic relations.
Canada announced last month that it was bringing home the families of its diplomats in Cuba after a year-long investigation into the illness failed to reveal a cause.
Unlike their American counterparts, however, no Canadian envoy reported hearing any suspicious sound prior to falling ill.
"The cause (of their symptoms) remains unknown but could be human-made," the Canadian government concluded.