BELGRADE - Serbia's last major war crimes fugitive, a Croatian Serb wartime leader indicted for crimes against humanity during the 1991-95 Croatian war, has been arrested, a Serbian official told Reuters on Wednesday.Goran Hadzic was a key figure in the breakaway Krajina Serb republic in Croatia, and after the arrest of wartime General Ratko Mladic earlier this year, he was Serbia's last remaining figure sought by the United Nations war crime tribunal in the Hague.RELATED:Mladic removed from war crimes court after outburstMladic calls Bosnian genocide charges 'monstrous' lieA Serbian official confirmed the arrest but declined to give details. President Boris Tadic, who announced the arrest of Mladic in May, scheduled an urgent news conference for 11 a.m. (0900 GMT).Hadzic is charged with ordering the killing of hundreds and the deportation of thousands of Croats and other non-Serbs from the area.The European Union, which hailed Belgrade for finding Mladic in May, has continued to insist on the arrest of Hadzic for Serbia to make progress towards European Union membership.Hadzic lived openly in the northern Serbian city of Novi Sad until July 13, 2004, when The Hague sent an indictment and arrest warrant to Belgrade. He fled immediately, tipped off by nationalist hardliners in Serbia's security services.His escape was kept a secret for days, while relatives said he was at home and police denied having orders to arrest him. The Hague later made public surveillance pictures showing him leaving his house with a bag on the afternoon of July 13. In Serbia, Hadzic gained notoriety in the past for his involvement in murky deals including illegal exports of oak wood, wine as well as crude oil from an oil well which was under Serb control. He was frequently seen in the company of Zeljko "Arkan" Raznatovic, a paramilitary leader and the head of Belgrade's underworld at the time.