The International Committee of the Red Cross says it is worried about a hunger strike by a number of detainees at the US detention camp at Guantanamo Bay in Cuba.
In a rare public statement about the organisation's concerns, a spokesperson for the committee, Antonella Notario, described the situation as serious.
The US military says 28 prisoners are on hunger strike. But lawyers for some of the detainees say as many as 200 have refused food.
Lawyers have also accused camp officials of force-feeding inmates.
