He once boasted on television that his fighters would gouge out Croatian eyeballs with rusty shoehorns, but Vojislav Seselj, one of Serbia’s most notorious paramilitary leaders, finally faces justice when his trial begins today at the UN war crimes tribunal in The Hague.

Mr Seselj, 52, is accused of war crimes and crimes against humanity against non-Serbs during the Croatian and Bosnian wars of 1991-95. His Chetnik militia, named after the royalist Serbian guerrillas in the Second World War, was notorious for brutality, giving no quarter to civilians. Many in it were criminals released from prison by Slobodan Milosevic, the Serbian President, and were often drunk on the battlefield.

Mr Seselj’s men have laid down their arms but their ideology lives on in his extreme-nationalist Serbian Radical Party, which holds 82 seats in the 250-seat Serbian parliament and is polling some 30 per cent support with elections due in January.

Anton Nikiforov, spokesman for the prosecution at the International Criminal Tribunal for the Former Yugoslavia (ICTY), said: “This is one of the most significant trials from the prosecution’s perspective. It deals with an important leader of a Serbian political party, who is known for his extremist views. Seselj led a paramilitary unit which committed crimes in both Bosnia and Croatia.”

Born in Sarajevo, Mr Seselj claimed during the communist era that Bosnia and Montenegro were “invented” nations that had no right to exist. This earned him almost two years in prison in Zenica, Bosnia. His experiences there gave him a visceral loathing of Croats and Muslims. The late Warren Zimmerman, former US Ambassador to Yugoslavia, described him as “a psychopathic bully”.

The trial could reveal important details about the role of the Milosevic regime and the Serbian state in the bloody ethnic cleansing in Croatia and Bosnia. Mr Seselj told the author Tim Judah: “Milosevic organised everything. We gathered the volunteers and he gave us a special barracks, Bubanj Potok, all our uniforms, arms, military technology and buses. His key people were the commanders. Nothing could happen on the Serbian side without Milosevic’s orders or knowledge.”

Despite the support he received from Milosevic, Mr Seselj was loathed by the President’s wife, Mira Markovic, who he once suggested was not really a woman. But behind this political cabaret are some of the darkest atrocities of the Yugoslav wars, including ethnic cleansing, murder, deportation, torture and sexual assault.

Mr Seselj surrendered to the tribunal in February 2003 and arrived in The Hague in the same month. He pleaded not guilty to all charges. He is defending himself and his pre-trial hearings have been marred by repeated outbursts. He refused to attend a status hearing last week on the progress of his case and has been on hunger strike for much of this month.

There are fears that, if Mr Seselj dies while on hunger strike, it will trigger a political crisis in Serbia and the coalition Government, led by Vojislav Kostunica, the Prime Minister, could fall.

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