Canada to pull out diplomats' families

Canada announced Monday it was sending home the families of its diplomats in Cuba, after a year-long investigation into a mysterious illness afflicting Canadian and US officials failed to reveal a cause.

The number of Canadian envoys and family members with symptoms, meanwhile, has risen from eight to 10, a senior official told a media briefing. Twenty-seven had been tested.

"The cause (of their symptoms) remains unknown but could be human-made," the government concluded.

"Regular embassy operations will continue," it said.

Canadian and US authorities had initially suspected a "sonic attack" or a "mass psychosomatic incident," which led to heightened diplomatic tensions between Washington and the Caribbean island nation, but those are "now considered unlikely," the senior official said.

The symptoms included dizziness, headaches and a lack of ability to concentrate. 

American doctors and officials have pointed to "a new type of a possible acquired brain injury" outlined in a February Journal of the American Medical Association article by health experts at the University of Pennsylvania, who treated the US diplomats.

Canada has accepted that theory.