SARAJEVO, Bosnia -- A UN war crimes court convicted former Bosnian Serb leader Radovan Karadzic of genocide and nine other charges on Thursday for orchestrating a campaign of terror that left 100,000 people dead during the 1992-95 war in Bosnia, the worst carnage in Europe since the Second World War.

Karadzic was sentenced to 40 years in prison for his role in Serb atrocities that included the Srebrenica massacre in which 8,000 Muslim men and boys were slaughtered in Europe's worst mass murder since the Holocaust, and for directing the nearly four-year siege of Sarajevo.

In pronouncing the verdict, presiding Judge O-Gon Kwon said Karadzic and his military commander, Gen. Ratko Mladic, intended "that every able-bodied Bosnian Muslim male from Srebrenica be killed."

Karadzic, the judge said, was the only person in the Bosnian Serb leadership with the power to halt the genocide, but instead gave an order for prisoners to be transported from one location to another to be killed. In the carefully planned 1995 operation, Serb forces moved Muslim men and boys to sites around the Srebrenica enclave in eastern Bosnia and gunned them down before dumping their bodies into mass graves.

Upon hearing the sentence, the 70-year-old Karadzic slumped slightly in his chair, but otherwise showed little emotion. He plans to appeal the convictions.

The former leader, who was arrested in Serbia in 2008 after more than a decade in hiding, is the highest Bosnian Serb official to be sentenced by the Netherlands-based court.

Although 20 years in coming, the trial is hugely significant for the development of international law. Karadzic's conviction will likely strengthen international jurisprudence on the criminal responsibility of political leaders for atrocities committed by forces under their control.

"Victims and their families have waited for over two decades to see Karadzic's day of reckoning," Param-Preet Singh, senior international justice counsel at Human Rights Watch, said in a statement. "The Karadzic verdict sends a powerful signal that those who order atrocities cannot simply wait out justice."

UN Secretary-General Ban Ki-moon's deputy spokesman, Fanhan Haq, told reporters the judgment "sends a strong signal to all who are in positions of responsibility that they will be held accountable for their actions and shows once again that fugitives cannot outrun the international community's collective resolve to make sure that they face justice according to the law."

Karadzic had faced a total of 11 charges and a maximum life sentence. However, the court acquitted him of a second genocide charge, for a campaign to drive Bosnian Muslims and Croats out of villages claimed by Serb forces.

Prosecutors had sought a life sentence, but the court's chief prosecutor, Serge Brammertz, said 40 years amounted to the same thing for the aging Karadzic.

"Overall, we are satisfied with the outcome," Brammertz said, adding that prosecutors would carefully study the judgment before deciding whether to appeal the one genocide acquittal.

Karadzic had insisted he was innocent and claimed throughout the six-year court proceedings that his wartime actions were intended to protect the Serbs. Peter Robinson, part of Karadzic's legal team, said he would appeal.

"Dr. Karadzic is disappointed. He's astonished," Robinson told reporters. "He feels the trial chamber took inference instead of evidence in reaching the conclusions that it did."

The verdict and sentence were met with expressions of relief and satisfaction from Bosnian Muslims and anger by Serb nationalists, thousands of whom took to the streets of the Serbian capital, Belgrade, to protest.

In Sarajevo, Amra Misic, 49, said: "I took a day off to watch the verdict as I was waiting for this for 20 years. I wish him a long life."

In Bosnia, which has remained ethnically divided since the war, posters displaying Karadzic's photo and saying "We are all Radovan" were plastered on walls in several towns in the Serb-controlled part of the country.

"This was only the first half of the process," said Karadzic's daughter Sonja, expressing the prevailing sentiment among the Serbs that the UN court and the West in general are highly biased against them.

Bosnia's president, Bakir Izetbegovic, whose father led the Muslims during the war, said the verdict against Karadzic is a verdict to a "horrific ideology and policies." He said it was a "judgment about the past that is important for the future."

Izetbegovic said the ruling confirmed that crimes in Bosnia were systematically planned and executed.

"There is no punishment that can give any satisfaction to the victims, but the civilized world has still shown that they understand their suffering," he said. "The world has sent a message that no one will be cleared of responsibility for crimes."

Serbian President Slobodan Milosevic, accused of fomenting deadly conflicts across the Balkans as Yugoslavia crumbled in the 1990s, died in his cell in The Hague in 2006 before judges could deliver verdicts in his trial.

Karadzic was indicted along with Mladic in 1995, but evaded arrest until he was captured in Belgrade in July 2008. At the time, he was posing as a New Age healer, Dr. Dragan Dabic, and was disguised by a thick beard and shaggy hair.

Karadzic's trial was one of the final acts at the Yugoslav war crimes tribunal. The court, set up in 1993, indicted 161 suspects. Of them, 80 were convicted and sentenced, 18 acquitted, 13 sent back to local courts and 36 had the indictments withdrawn or died.

Three suspects remain on trial, including his military chief, Mladic, and Serb ultranationalist Vojislav Seselj. Eight cases are being appealed and two defendants are to face retrials. The judgment in Seselj's case is scheduled for next Thursday.

Corder reported from The Hague. Associated Press writers Dusan Stojanovic and Jovana Gec contributed from Belgrade, Serbia