Radovan Karadzic led a genocidal campaign to make Bosnian Muslims "disappear from the face of the earth" and carve out a mono-ethnic state for Bosnian Serbs, war crimes prosecutors told a U.N. tribunal Tuesday.

In opening statements, prosecutors painted a picture of the former Bosnian Serb leader as a supreme commander single-mindedly pursing a campaign of "ethnic cleansing" during the 1992-95 Bosnian war that killed an estimated 100,000 people.

They spoke to empty chairs on the defendant’s side of the court as Karadzic, who denies all the charges, boycotted the trial at the International Criminal Tribunal for the former Yugoslavia for a second day.

"The Supreme Commander explained in October 1991 what was coming for Sarajevo: ’Sarajevo will be a black cauldron where Muslims will die. They will disappear, that people will disappear from the face of the earth’," senior prosecutor Alan Tieger cited Karadzic as saying in an intercepted call.

He was referring to the 43-month siege of Sarajevo that began in 1992 and killed an estimated 10,000 people as the former Yugoslavia was torn apart in the 1990s by Serbs, Croats and Muslims fighting for land.

"The supreme commander had directed his forces in a campaign to carve out a mono-ethnic state within his multi-ethnic country," Tieger said.

"This case, your honours, is about that supreme commander. A man who harnessed the forces of nationalism, hatred and fear to implement his vision of an ethnically separated Bosnia -- Radovan Karadzic."

In addition to maps, slides and intercepted phone calls, Tieger showed several videos of Serbian snipers shooting Sarejevo citizens, as well as others of Karadzic on the hills overlooking the city, observing and directing the siege.

He promised to provide witnesses and testimony during the trial showing Karadzic’s active involvement in Sarejevo and other campaigns to wipe out minorities.

As prosecutors began their case Tuesday, Biljana Plavsic, Karadzic’s successor as Bosnian Serb president, left a Swedish prison and arrived in Belgrade after winning early release from her sentence for committing war crimes.