Radovan Karadzic grew a long, white beard to conceal his identity and even managed to openly practice alternative medicine while in hiding, officials said Tuesday in revealing details of the war crimes fugitive's capture after a decade on the run.

Karadzic, the wartime leader of Bosnian Serbs, was arrested Monday night in a Belgrade suburb, officials said. A judge has ordered his transfer to the U.N. war crimes tribunal in The Hague, Netherlands, to face genocide charges, war crimes prosecutor Vladimir Vukcevic said.

Karadzic has three days to appeal the ruling. His lawyer, Sveta Vujacic, said he will launch the process to fight extradition on the last day, Friday, to thwart authorities' wishes for his immediate transfer.

Karadzic — accused of masterminding the deadly wartime siege of Sarajevo and the executions of up to 8,000 Muslims in Srebrenica during Bosnia's 1992-95 war, Europe's worst massacre since World War II — had topped the tribunal's most-wanted list for years.

Government official Rasim Ljajic said Karadzic, once known for his distinctively coifed hairdo, was unrecognizable.

"His false identity was very convincing," Vukcevic said. "Even his landlords were unaware of his identity."

Karadzic used a false name, Dragan Dabic, Ljajic said.

The editor in chief of Belgrade's "Healthy Life" magazine, Goran Kojic, said he was shocked when he saw the photo of Karadzic on TV, recognizing him as a regular contributor to the publication.

"It never even occurred to me that this man with a long white beard and hair was Karadzic," Kojic said.

Karadzic's whereabouts had been a mystery since he went on the run in 1998, with his hideouts reportedly including monasteries and mountain caves in remote eastern Bosnia.

Serbian security services found Karadzic, 63, on Monday while looking for another top war crimes suspect facing genocide charges, Bosnian Serb wartime commander Gen. Ratko Mladic, Ljajic said.

Karadzic "was arrested Monday evening near Belgrade while changing locations," he said. "International pressure was to arrest Mladic, and a few had expected that Karadzic would be captured."

A judge finished interrogating Karadzic on Tuesday and issued the order for his extradition.

Ljajic refused to reveal more details about his arrest, saying Karadzic's movements are being analyzed and will be kept secret until Mladic's capture. "We are absolutely determined to finish this job," he said.

Karadzic — disguised by the bushy beard and glasses — managed to move freely while living in a new part of Belgrade and working at a private clinic, Ljajic said, holding up a photo of a much thinner-looking Karadzic.

Governments worldwide hailed the arrest of the man described by the tribunal as the mastermind of "scenes from hell, written on the darkest pages of human history."

German Chancellor Angela Merkel called it a "historic moment."

"The victims need to know: Massive human rights violations do not go unpunished," she said in Berlin.

European Union foreign ministers meeting in Brussels said the arrest sets Serbia firmly on the path toward EU membership.

"We have waited for this for 13 years. Finally. Finally," said French Foreign Minister Bernard Kouchner said in Brussels. "This is a very good thing for the rapprochement of Serbia with the European Union."

In Sarajevo, Bosnian Muslims rushed into the streets Monday night to celebrate the news of Karadzic's arrest.

"This is a very important day for the victims who have waited for this arrest for over a decade," said the tribunal's head prosecutor, Serge Brammertz. "It clearly demonstrates that nobody is beyond the reach of the law and that sooner or later all fugitives will be brought to justice."

During the siege of Sarajevo that began in 1992, Bosnian Serb troops starved, sniped and bombarded the city center, operating from strongholds in Pale and Vraca high above the city and controlling nearly all roads in and out.

Inhabitants were kept alive by a thin lifeline of food aid and supplies provided by U.N. donors and peacekeepers. Walking down the street to shop for groceries or driving down a main road that became known as "Sniper Alley" was a risk to their lives.

The siege was not officially over until February 1996. An estimated 10,000 people died.

The international tribunal indicted Karadzic on genocide charges in 1995. The psychiatrist and self-styled poet-turned-hardline Serbian nationalist continue to wield behind-the-scenes power over Bosnian Serbs, occasionally appearing in public before going into hiding three years later.

The worst massacre was in Srebrenica in 1995, when Serb troops led by Mladic overran the U.N.-protected enclave sheltering Bosnian Muslims. Mladic's troops rounded up the entire population and took the men away for execution.

By war's end in late 1995, an estimated 250,000 people were dead and another 1.8 million driven from their homes.

Under the U.N. indictment, Karadzic faces 11 counts of genocide, war crimes, crimes against humanity and other atrocities committed between 1992 to 1996.

He would be the 44th Serb suspect sent to the tribunal in The Hague. The others include former President Slobodan Milosevic, who died there in 2006 while on trial.