|PIC1|Bosnian Serb wartime president Radovan Karadzic, wanted for planning and ordering Europe's worst atrocities since World War Two, has been arrested after 11 years on the run.

"Karadzic was located and arrested," President Boris Tadic said in a terse statement on Monday night that Bosnian Muslims had begun to despair of ever hearing.

It brought people out in the night onto the streets of Sarajevo, the city his troops shelled mercilessly during a 43-month siege, to celebrate the capture of the man charged with authorising the slaughter of 11,000 of their fellow citizens.

"I called and woke up my whole family," said Sarajevo resident Fadil Bico, as cars streamed through the streets honking horns and Bosnian state radio played excerpts of Karadzic's wartime hate speeches.

Serbian government sources said Karadzic was arrested on Monday but had been under surveillance in Serbia for several weeks, after a tip-off from a foreign intelligence service.

He did not resist arrest. His lawyer, Svetozar Vujacic, told reporters Karadzic was arrested on Friday night, while taking a bus between two suburbs of Belgrade, and had been held for three days before the announcement.

Details of the arrest and the timetable of his likely extradition were expected at a news conference at 11 a.m. (10 a.m. British time).

The last published pictures of Karadzic date from the late 1990s. Investigators conducted a formal identification process, including DNA testing, before interviewing him overnight. His lawyer said he looked the same, with his trademark grey, floppy hair, but had lost weight.

Karadzic's arrest was one of the main conditions of Serbian progress towards European Union (EU) membership, which most of its people desire. One-third say they oppose joining until the bloc stops supporting the secession of the province of Kosovo.

Richard Holbrooke, former U.S. Balkan troubleshooter during the wars of the 1990s' described Karadzic as the Osama bin Laden of Europe, "a real, true architect of mass murder".

Karadzic went underground more than a year after Holbrooke negotiated the 1995 Dayton accords that ended the war in Bosnia and NATO deployed a huge force of peacekeepers in early 1996.

TWO MORE SUSPECTS AT LARGE

His arrest leaves two war crimes suspects still wanted by the Hague tribunal. But it should be enough to secure Serbia closer ties with the European Union (EU) and possibly the status of EU membership candidate state this year.

Karadzic was indicted along with his army commander, General Ratko Mladic, for genocide at Srebrenica, where some 8,000 unarmed Bosnian Muslim males were rounded up and murdered and bulldozed into mass graves in July 1995.

"The arrest of Radovan Karadzic is confirmation that every criminal will eventually face justice," said Munira Subasic, head of a Srebrenica widow's association.

"I hope that people who had to keep quiet because of Karadzic will start revealing the locations of mass graves and let us find the truth about our beloved ones," she said.

The arrest came on the eve of a meeting of EU foreign ministers scheduled to discuss closer relations with Belgrade following the formation of a new pro-Western government.

"It proves the determination of the new Serbian government to achieve full cooperation with the ICTY (International Criminal Tribunal on the former Yugoslavia). It is also very important for Serbia's European aspirations," said European Commission President Jose Manuel Barroso.

EU members who insist Serbia must hand over all war crimes suspects are likely to see it as proof that Karadzic's fellow genocide suspect, the fugitive wartime commander Mladic can also be seized if Belgrade has the political will to face down hardline nationalists.

The new government is an odd-couple alliance of President Tadic's pro-Western Democratic Party and the Socialists of the late Slobodan Milosevic, who died in detention at the Hague war crimes prison before del Ponte could obtain a conviction.

UN WELCOMES ARREST

U.N. Secretary-General Ban Ki-moon praised Serbian authorities for taking a "decisive step toward ending impunity" of those indicted for crimes in Balkan conflicts.

"This is a historic moment for the victims, who have waited 13 years for Mr. Karadzic to be brought to justice," he said in a statement released by the United Nations.

The EU, initially worried about where the Socialists stood on the Hague tribunal, welcomed the capture, which apparently took place in Belgrade.

Some officials said they expected Karadzic to be taken swiftly to The Hague, but a senior judicial source in Serbia told Reuters he would likely stay in the country for at least three days while his lawyers appeal to fight his extradition.

Karadzic is still seen by militant nationalists as a national saviour following the collapse of Yugoslavia.

"This is payback to the EU for bringing this new government to power," said Aleksandar Vucic of the nationalist Radicals, one of Serbia's strongest parties. "Karadzic is a Serbian hero. There will be a strong backlash."

Karadzic's place of hiding had been a constant subject of international speculation since he went underground in 1997. The West had long suspected Belgrade of failing to press the search, but the new government had signalled it wanted to comply.