Shortly after hearing his fate, former Bosnian Croat military chief Slobodan Praljak shouted "I am not a war criminal!" and lifted a small vial of liquid to his lips.
He tilted his head back and swallowed.
A short time later, he told the confused court - and the judge who'd affirmed his 20-year sentence - "I just drank poison."
His death was reported by Croatian state TV later on Wednesday. The Hague did not immediately confirm the death or other details.
It was a defiant final act for the 72-year-old accused of murdering Muslims and committing other atrocities two decades ago in a failed attempt to create a Bosnian Croat ministate, according to the Associated Press.
The appeal of Praljak was one of the final matters for the International Criminal Tribunal for the former Yugoslavia. Praljak is accused of using violence and murder to drive out Muslims.
Praljak "facilitated the murder of Muslims who did not belong to any armed force, and the destruction of property in Stupni Do in October 1993," according to the United Nations.
He was indicted in March 2004 and pleaded not guilty a month later. But on May 29, 2013, he was found guilty of all charges.
The appeal was the only thing standing between Praljak and possibly spending the rest of his life in prison. The tribunal is expected to conclude next month.
For now, it is suspended as questions swirl around Praljak's actions, including what he swallowed and how he was able to sneak it into a war tribunal.
A decade's worth of hearings was a reminder of the complex web of ethnic tensions that fueled fighting in Bosnia, the AP reported. Those tensions continue to create friction today.
For Praljak, the calculus was much simpler: The appeal was the last thing standing between him and possibly spending the rest of his life behind bars.
The tribunal turned over some of the convictions related to him. But the heaviest ones remained, along with the 20-year sentence - and the shame of being branded a war criminal.