A Bosnian Croat war criminal claimed to take poison while in court.

Slobodan Praljak appeared to drink from a small vial as his sentence was upheld.

Praljak was trying to appeal a 20-year sentence for crimes during the Bosnian War.

A war criminal who commanded forces in the Bosnian conflict of the early 1990s has died after drinking a vial of what he called poison in court as he was told his 20-year prison sentence would be upheld.

The death of Slobodan Praljak, a Bosnian Croat military leader, was announced by Croatian state TV, according to the Press Association.

Croatian Prime Minister Andrej Plenkovic also confirmed the death and offered condolences to his family, the Associated Press reported.

The 72-year-old was convicted four years ago of war crimes in East Mostar during the 1992-1995 Bosnian War.

He appeared in a United Nations court in The Hague on Wednesday trying to appeal the 2013 sentence.

According to the BBC, he had failed to make serious efforts to stop soldiers from rounding up Muslims in Prozor and failed to act on information about murders and attacks on people and property in East Mostar during the war.

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As his sentence was being read, Praljak yelled, according to CNN: “Slobodan Praljak is not a war criminal. I reject your verdict with contempt.”

He then tipped his head back, appeared to drink from a small vial, and said: “What I drank was poison,” according to Deutsche Welle.

You can watch the moment unfold in the clip below:

The judge immediately ordered the court to be taken into private session and the proceedings were suspended, the BBC reported. The court’s live video feed also went dark shortly after the incident.

The same tribunal last week sentenced Serbian Gen. Ratko Mladić to life in prison for carrying out a host of war crimes, including genocide.

This is not the first time generals tried by the UN court have killed themselves during trial. Slavko Dokmanovic and Milan Babić – both Croatian Serbs accused of war crimes in the Bosnian conflict – were found dead in their prison cells in 1998 and 2006.