Bosnian Serb war crimes suspect Radovan Karadzic, one of the world's most wanted men, has been arrested in Serbia after more than a decade on the run.
He has been brought before Belgrade's war crimes court, in accordance with a law on cooperation with the Hague Tribunal, the Serbian presidency said.
The Bosnian Serb wartime political leader disappeared in 1996.
He had been indicted by the UN tribunal for war crimes and genocide over the 1995 massacre at Srebrenica.
His wartime military leader, Ratko Mladic, remains at large.
Mr Karadzic's arrest was welcomed by war crimes prosecutors in The Hague as a "milestone".
"Radovan Karadzic was located and arrested tonight" by Serbian security officers, a statement by the office of President Boris Tadic said, without giving details.
"Karadzic was brought to the investigative judge of the War Crimes Court in Belgrade, in accordance with the law on cooperation with the International Criminal Tribunal for the former Yugoslavia [ICTY]."
Serbian government sources told Reuters news agency he had been under surveillance for several weeks, following a tip-off from a foreign intelligence service.