Bosnian Croat former military leader Slobodan Praljak died on Wednesday in a hospital after “drinking a liquid” during his appeal judgement by UN war crimes judges, a spokesman for the tribunal said.

“One of the six defendants… passed away today in the HMC hospital in The Hague,” said court spokesman Nenad Golcevski. Immediately after sentence was passed on Praljak “he drank a liquid while in court and quickly fell ill,” he added.

Efforts were made to give him medical treatment and he was “transported to the hospital where he passed,” Golcevski said.

Slobodan Praljak yelled, ‘I am not a war criminal!’ and drank a dark liquid from a small bottle seconds after losing his appeal against a 20-year prison sentence at the International Criminal Tribunal, in the Netherlands.

‘I just drank poison,’ he added. ‘I am not a war criminal. I oppose this conviction.’

Praljak, 72, is one of six Croatian politicians sentenced to jail for their involvement in a campaign to drive Muslims out of a would-be Bosnian Croat mini-state in Bosnia in the early 1990s.

His lawyer shouted out ‘my client has taken poison’ before judge Carmel Agius suspended the hearing and the courtroom was closed.

Moments later ambulance crews arrived at the scene and a helicopter began hovering overhead.

Several emergency rescue workers rushed into the building carrying equipment in backpacks, while court officials called for calm.

A spokesman for the tribunal confirmed he died after ‘he drank a liquid while in court and quickly fell ill’.