The United States Friday raised the number of embassy officials affected by mysterious covert attacks in Cuba to 24 but said the update did not reflect new attacks.
"Based on continued assessments of US Government personnel, we can confirm 24 persons have experienced health effects from the attacks," State Department spokeswoman Heather Nauert said.
"We can't rule out additional new cases," she added.
The US has not directly blamed Cuba for the attacks -- but has emphasized its responsibility to ensure the safety of foreign diplomats in its territory.
The Americans also suggest the attacks were carried out using a covert acoustic device.
The most recent attack was at the end of August, according to the State Department. But Cuban Chancellor Bruno Rodriguez maintained Cuba had found no evidence they had happened early this month.
Those affected have exhibited physical symptoms including hearing loss, cognitive issues, and difficulty sleeping.
In response, the US withdrew more than half the personnel from the US embassy in Cuba and ordered the expulsion of 15 Cuban diplomats in the United States.