The Serbian police on Thursday morning arrested a man under the name of Milorad Komadic, who is suspected to be Ratko Mladic, a wartime Serbian leader wanted for war crimes.
The checking of the arrestee's identity is under way, the Belgrade-based B92 television reported.
Mladic is accused of war crimes including genocide and crimes against humanity which Bosnian Serb forces committed in Bosnia and Herzegovina during the war in the first half of the 1990s. He is wanted by the UN tribunal in The Hague.
Serbia's President Boris Tadic is to hold an emergency news conference at 1300 hrs.
