A war crimes appeal hearing in The Hague has been suspended after the accused drank what he said was poison upon hearing the verdict, BBC reports.
Slobodan Praljak was one of six former Bosnian Croat political and military leaders up before the court, according to BBC.
He was sentenced to 20 years' imprisonment in 2013 for crimes in East Mostar.
On hearing that his sentence had been upheld, he told the judge, "I have taken poison".
The six were appearing in court for the final appeals judgment to be handed down by the Yugoslav Tribunal.
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The judge immediately ordered the curtains be brought down and the proceedings suspended.
Before they were lowered the courtroom could be seen in a state of confusion, the BBC's Anna Holligan reports from The Hague.
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