Transcript for Bosnian war criminal drinks poison in court

Next tonight here, to that moment in court making global headlines tonight. A convicted war criminal suddenly drinking poison and then shouting a message to the judge. Here's ABC's Ian Pannell. Reporter: Standing silent, this Hague judge telling sloboban praljak his 20-year sentence for war crimes during the bosnian war would be upheld. Mr. Praljak, you may be seated. Reporter: His response -- shocking. Stop, please. Reporter: The 72-year-old lifting a small brown bottle to his lips, swallowing poison for all the world to see before saying, calmly, to the courtroom, "I have taken poison." We suspend. Please, the curtains. Reporter: Attempts to save praljak failed. He was convicted for his role in a campaign to drive muslims out of bosnia and create an ethnically pure croat state during the bosnian war in the '90s. 100,000 died and more than 2 million displaced during the three-year war. So, another remarkable day in a court that's already seen its fair share of dramas, as war criminals are sentenced for their part in that conflict. As you would expect, questions now being asked about how he was able to smuggle poison into court. ABC news learning tonight that security procedures are being tightened up.

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