Four more US diplomats working in Geneva and Paris have fallen ill with a suspected neurological illness known as "Havana syndrome", US media report. Three diplomats became sick in the Swiss city and one in the French capital last summer, with some 200 people affected over five years.
Secretary of State Antony Blinken said the American government was working to get to the bottom of the mystery. There are fears an adversary may have targeted diplomats with microwaves. Mr Blinken said the issue had been raised with Russia but no determination had been made.
[...] A more innocent, but also unproven, theory is that those who got sick suffered from a mass condition brought on by some stressful underlying situation.