The U.N. International Criminal Tribunal for the former Yugoslavia, based in the Hague, Netherlands, accused him of genocide, crimes against humanity, and war crimes for the massacre of Muslims by Bosnian Serb forces in eastern Bosnia and the relentless four-year siege of Sarajevo.
On Thursday evening, Mladic walked haltingly into a closed-door extradition hearing in Belgrade, where he asserted through his attorney that he would not answer to the U.N. tribunal's authority.
He wore a jacket and a baseball hat and carried what appeared to be a towel. He could be heard on state TV saying "good day" to someone in the courtroom.
His lawyer, Milos Saljic, said the judge cut short the questioning because Mladic's "poor physical state" left him unable to communicate.
"He is aware that he is under arrest, he knows where he is, and he said he does not recognize the Hague tribunal," Saljic said. He said Mladic needed medical care and "should not be moved in such a state."
Belgrade B-92 radio said one of Mladic's arms was paralyzed, probably from a stroke.
Deputy war-crimes prosecutor Bruno Vekaric said Mladic was taking a lot of medicine but "responds very rationally to everything that is going on."
Extradition proceedings could take a week or more before his likely transfer to the Hague, where he faces life in prison if convicted. The U.N. court has no death penalty.
Judge Fouad Riad of the U.N. tribunal said there was evidence against Mladic of "unimaginable savagery."
"Thousands of men executed and buried in mass graves, hundreds of men buried alive, men and women mutilated and slaughtered, children killed before their mothers' eyes, a grandfather forced to eat the liver of his own grandson," Riad said during Mladic's 1995 indictment in absentia.
International-law experts hope the arrest will send a message to figures such as Libya's Moammar Gadhafi that no leader charged with a war crime can expect to escape justice forever. "Impunity has really been withdrawn from war criminals," said Richard Goldstone, the prosecutor in the 1995 indictment.
President Obama, meeting with other world leaders at the Group of Eight summit in France, hailed the arrest, expressing hope that "the families of Mladic's victims find some solace" in it.
U.N. Secretary-General Ban Ki-moon said it marked "an important step in our collective fight against impunity."
Serbia's government, which has changed mightily while Mladic was at large, banned all public gatherings Thursday and tightened security to prevent ultranationalists from making good on pledges to pour into the streets in protest.
The Serbian Radical Party called Mladic a "hero," and the extreme-right group 1389 called the arrest "treason." Hundreds of pro-Mladic demonstrators in the northern city of Novi Sad tried to break into the offices of the governing Democratic Party but were prevented by riot police.
President Boris Tadic appeared jubilant at a news conference announcing Mladic's capture. "We have ended a difficult period of our history and removed the stain from the face of Serbia and the members of our nation wherever they live," he said.
A Serbian official close to Tadic, speaking on condition of anonymity, said the president had personally overseen the arrest operation, and compared it to Obama's involvement in the hunt for Osama bin Laden.
But the raid in Lazarevo, 60 miles northeast of Belgrade, was no Navy SEAL operation, and Serbian intelligence agents didn't have to fire a shot. Mladic had two pistols with him in the single-story yellow brick house but put up no resistance, officials said.
"They didn't even wake us up," said a resident who identified himself only as Zoran.
He and other residents of the village of 2,000 insisted they had no idea Mladic was living in their midst - not that they would have minded.
"I'm furious," Zoran said. "They arrested our hero."
Many residents came out to defend Mladic, waving Serb and Russian flags. They blocked the road with a trailer, demanded that no camera lenses be pointed at the house, and told journalists to leave. A sign reading "Mladic Hero" rose at the entrance of the village.
The arrest releases Serbia from the widespread suspicion that it was protecting Mladic. U.N. war-crimes prosecutor Serge Brammertz was due in June to give the United Nations a report critical of Serbia's lack of cooperation with the hunt for Mladic and other fugitives.
The Netherlands had used such reports to justify blocking Serbia's efforts to join the EU, and the arrest could help Serbia shed its image as a pariah state that sheltered the men responsible for the worst atrocities of the Balkan wars.
Serbia still faces many obstacles to EU membership, and might also have to recognize the independence of Kosovo, its former province, and capture another war-crimes fugitive, Goran Hadzic, a former leader of Serbs in Croatia.
Among the horrors Mladic is charged with, foremost is the July 1995 slaughter of up to 8,000 Muslim males in Srebrenica, which was supposed to be a safe zone guarded by Dutch peacekeepers. Mladic seized the town and handed candy to Muslim children, assuring them everything would be fine and patting a boy on the head. Hours later his men began days of killing, rape, and torture.
The Dayton accords brought peace to Bosnia in 1995, and the next year Mladic was dismissed from his post. He continued to live in Bosnia, until his trail grew too hot and he moved to Belgrade in the late 1990s, living free in a posh villa.
Even as Mladic allies such as Radovan Karadzic and Slobodan Milosevic were brought to the Hague, Mladic was idolized and sheltered by ultranationalists and ordinary Serbs despite a $14 million Serbian government bounty, plus $5 million offered by the U.S. State Department.
When Serbia ousted strongman Milosevic in 2000, the new pro-democracy authorities signaled they might hand Mladic over to the tribunal. He went mostly underground in 2002.
The Charges Mladic Faces
Under an indictment last amended in 2009, the U.N. war-crimes tribunal has filed these charges against Ratko Mladic:
One count of genocide, in Srebrenica and elsewhere
One count of complicity in genocide.
One count of persecutions on political, racial, and religious grounds, extermination, murder, deportation, and crimes against humanity.
One count of murder, unlawfully inflicting terror upon civilians, cruel treatment, attacks on civilians, taking of hostages, violating the laws or customs of war.
SOURCE: Associated Press
The World's Most Wanted
Key people still being sought, after the killing of Osama bin Laden and the capture of Ratko Mladic:
Omar al-Bashir: President
of Sudan. Accused of
war crimes in Darfur.
Ali Kushayb: A commander of the Sudanese government-backed janjaweed militia. Accused of ordering killings, rapes.
Joseph Kony: Leader of the brutal rebel group the Lord's Resistance Army, known for vicious attacks against civilians in Uganda.
Jean Bosco Ntaganda: Congo warlord accused
of war crimes including a 2002 ethnic massacre and forcing children to fight.
Ayman al-Zawahiri: Al-Qaeda deputy indicted for his alleged role in the 1988 bombings of two U.S. embassies in Africa.
Anwar al-Awlaki: U.S.-born cleric who is one of al-Qaeda's most prominent English-language radicals.
Adam Yahiye Gadahn: Indicted in California, accused of treason and support to al-Qaeda.
Fahd Mohammed Ahmed al-Quso: Under U.S. indictment for his alleged role in the 2000 USS Cole bombing in Yemen, where he is thought to be.
Jamel Ahmed Mohammed Ali-Badawi: Wanted in the Cole bombing. Fled Yemeni custody in 2006.
World War II
Alois Brunner: The most important unpunished Nazi war-crimes suspect who may still be alive. Accused of helping to deport tens of thousands of Jews across Europe. Last seen in Syria in 2001.
Dr. Aribert Heim: Allegedly worked in Buchenwald, Mauthausen, and other concentration camps, where he is accused of murdering hundreds by lethal injection.
SOURCES: Interpol, FBI,
and the Simon Wiesenthal Center.