THE HAGUE, Netherlands (CNN) -- Former Bosnian Serb leader Radovan Karadzic was in U.N. custody at The Hague on Wednesday, preparing for his first court appearance more than 13 years after he was first indicted for war crimes, genocide, and crimes against humanity.
Karadzic, 63, arrived at The Hague in the morning after his extradition from Serbia. He will receive a medical check and be informed of the court's procedures and then go to the cell where he will stay during the trial.
Officials at the International Criminal Tribunal for the Former Yugoslavia will also give Karadzic a legal briefing that outlines his rights and options for defense.
The first indication of how Karadzic plans to plead will come at 4 p.m. (10 a.m. ET) Thursday, when Karadzic appears in court for the first time. He can enter a plea or defer a plea for as long as 30 days.
Chief Prosecutor Serge Brammertz said Karadzic's arrest last week after more than a decade on the run is important for the victims of his alleged crimes and for international justice.
"It clearly demonstrates that there is no alternative for the arrest of war criminals and that there can be no safe haven for fugitives," Brammertz said.
The tribunal has indicted Karadzic on 11 charges including genocide, crimes against humanity and war crimes, which Brammertz called "the most serious crimes under international law." Watch the chief prosecutor's statement »
The charges stem from the 1992-95 war in Bosnia-Herzegovina, when Karadzic was president of a breakaway Serb republic.
The tribunal accuses Karadzic of leading a campaign that killed thousands of men, women and children, mainly Bosnian Muslims and Bosnian Croats who were killed by Serbs as part of a violent effort to rid the region of non-Serbs.
Forces under Karadzic's command rounded up tens of thousands of non-Serbs and held them in camps where, an indictment says, the Serbian forces "tortured, mistreated, sexually assaulted and killed non-Serbs," the tribunal said Wednesday.
"The indictment also charges Karadzic with responsibility for a protracted campaign of shelling and sniping of civilian areas of Sarajevo, killing and wounding thousands of civilians, including children and the elderly," a tribunal statement said.
Serbian authorities arrested him July 21 in Belgrade, Serbia, after more than a decade on the run -- a time during which he disguised himself by growing a long white beard and mustache and re-invented himself as a practitioner of alternative medicine.
Brammertz gave rare praise to Serbian authorities, saying they deserve "full credit" for apprehending Karadzic.
"This arrest is a major achievement of Serbia's cooperation with the tribunal," he said.
Thursday's court appearance will offer the public the first chance to see Karadzic since his arrest. Until now, the public has only seen old photographs and videos of him in disguise.
The actual trial will not begin for several months, Brammertz said. Watch what awaits Karadzic »
Karadzic's lawyer in Belgrade said last week that his client planned to defend himself at the tribunal. Brammertz said he doesn't know whether Karadzic will choose to represent himself, but he advises against it.
"It will be, at the end of the day, up to the judges to decide if they allow self-representation or not," Brammertz said. "As far as the prosecution is concerned, already in the past we have objected and mentioned the difficulties of going with self-representation, especially if you speak about very complex cases, very complex legal questions where legal counsel is in our minds a very important advantage."
The Bosnian war was Europe's bloodiest conflict since World War II and the longest of the wars spawned by the breakup of Yugoslavia in the early 1990s. Backed by the government of then-Yugoslav President Slobodan Milosevic, Bosnian Serb forces seized control of more than half the country and launched a campaign against the Muslim and Croat populations that introduced the term "ethnic cleansing" to the world.
Karadzic was removed from power in 1995, when the Dayton Accords that ended the Bosnian war barred anyone accused of war crimes from holding office. Though he portrayed Serbs as victims, Karadzic is accused of responsibility for the massacre at Srebrenica, a U.N. "safe area" Serb troops overran in July 1995.
Nearly 8,000 Bosnian Muslim men and boys were killed at Srebrenica, the worst European massacre since World War II.
Milosevic died in March 2006 while on trial at The Hague. The highest-ranking figure to remain at large is Gen. Ratko Mladic, the Bosnian Serb military commander during the Bosnian war.
Milosevic was transferred to the tribunal in June 2001, and his trial began the following spring. When he died in March 2006, Milosevic had been on trial for more than four years.
Brammertz said he hoped to learn lessons from the way the Milosevic trial proceeded, perhaps not allowing Karadzic's case to run as long.
"We intend, of course, to use the pretrial phase to make a certain number of motions to the judges in order to have written evidence accepted, to have adjudicated facts accepted, which means that we hope that the amount of evidence to be presented in court therefore will be reduced," he said.
"It will be a complex trial as I said," he added. "Do not expect a trial taking only a very short period. But we are fully aware of the importance to be efficient in this regard."
CNN's Alessio Vinci and Nic Robertson contributed to this report
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