The U.S. State Department has brought a group of diplomats home from Guangzhou, China, over concerns they were suffering from a mysterious malady that resembles a brain injury and has already affected U.S. personnel in Cuba, its spokeswoman said on Wednesday.

After confirming one government employee had “suffered a medical incident” in the southern Chinese city, the department deployed a team to screen employees and family members at its consulate there, spokeswoman Heather Nauert said in a statement.

“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,”

Nauert said.

“Medical professionals will continue to conduct full evaluations to determine the cause of the reported symptoms and whether the findings are consistent with those noted in previously affected government personnel or possibly completely unrelated,” she said.

The New York Times reported on Wednesday that the State Department had evacuated at least two Americans who fell ill after hearing strange noises in China.

Last year, 24 U.S. government employees and family members in Cuba displayed the symptoms, which were similar to those related to concussions and mild traumatic brain injury, according to the State Department.

The illnesses among the American diplomats stationed in Havana heightened tensions between the old Cold War foes.

Secretary of State Mike Pompeo released a statement on Tuesday saying the department established a task force last month “to direct a multi-agency response to the unexplained health incidents.”

“The precise nature of the injuries suffered by the affected personnel, and whether a common cause exists for all cases, has not yet been established,” Pompeo said. (Reuters)