The war crimes trial of former Yugoslav President Slobodan Milosevic has been interrupted because he is suffering "dangerously high" blood pressure.
Mr Milosevic has been on trial in The Hague since February 2002
There is also a risk of cardio-vascular attack, according to a medical report read out at The Hague tribunal.
Mr Milosevic, who faces charges of genocide and other crimes against humanity, has not missed a day of court since he was allowed to defend himself.
One defence witness has refused to give evidence while he is absent.
The tribunal judges charged former Kosovo Serb leader Kosta Bulatovic with contempt of court for refusing to be cross-examined by prosecutors without Mr Milosevic in court.
The trial at the International Criminal Tribunal for the former Yugoslavia has been sitting for three years, interrupted by the frequent ill-health of Mr Milosevic, 62, who has a heart condition.
Before he won the right to conduct his own defence last year, proceedings had been interrupted 15 times.
A BBC correspondent at the tribunal says judges have asked the standby defence lawyers to start preparing the next witness in case Mr Milosevic remains ill.
The lawyers have said in the past that they cannot defend Mr Milosevic properly as he refuses to co-operate with them.
Mr Milosevic faces more than 60 charges of war crimes and crimes against humanity for his alleged central role in the wars in Bosnia, Croatia and Kosovo during the 1990s.
He also faces genocide charges over the 1992-95 Bosnia war, in which 200,000 people died.
He has been given 150 days to complete his case, at the rate of three hearings per week, with no time added on for time lost through illness.
Mr Milosevic was in office for 13 years until 2000. He faces life imprisonment if found guilty.