The UN tribunal sentenced the former head of the Bosnian Serb parliament to 27 years in prison on Wednesday for a campaign of ethnic cleansing against Bosnian Muslims and Croats during the 1992-95 Bosnian war.
Judge Alphons Orie pronounced Momcilo Krajisnik guilty of murder, extermination, deportation, persecution and forced transfer of non-Serb civilians, but said it had not been proved that he intended to commit genocide.
Captured by NATO-led peacekeepers near Sarajevo in 2000, the former right-hand man to Bosnian Serb wartime leader Radovan Karadzic went on trial in February 2004 and pleaded not guilty to all counts. His lawyers had sought his acquittal.
"Krajisnik wanted the Muslim and Croat populations moved out of Bosnian-Serb territories in large numbers, and accepted that a heavy price of suffering, death and destruction was necessary to achieve Serb domination," Judge Orie said.
In one attack, Orie said, a paramilitary group used spiked metal bars and chains to assault Muslim detainees, who were also forced to beat each other. One man had his ear cut off, others had their fingers cut off and men were sexually mutilated.
Krajisnik, 61, was one of the most senior politicians on trial in The Hague since the death earlier this year of former Yugoslav President Slobodan Milosevic, just months before his marathon trial had been expected to conclude.
A former economist, Krajisnik headed the parliament of the breakaway Bosnian Serb republic during the war, and was part of the presidency that controlled the army together with Karadzic and former Bosnian Serb President Biljana Plavsic.