Serbian police raided several locations Monday in search of former general Ratko Mladic, the most-wanted Balkans war crimes suspect, local media reported, according to dpa. The six-hour special-police operation in the town of Valjevo included a company that makes windows and bottled water whose owner is suspected of contacts with alleged war criminals. Valjevo, 70 kilometres south-west of Belgrade, has been mentioned as one of Mladic's possible hiding places. Capturing Mladic and extraditing him to the UN war crimes tribunal is the key remaining condition for Serbia's further progress toward European Union membership. The raid came a week before chief war crimes prosecutor Serge Brammertz is due to visit Belgrade. After his November 17-18 trip, Brammertz will submit a report to the UN Security Council. The Hague-based tribunal has charged Mladic with genocide and other crimes against humanity for his role as the commander of the Bosnian Serb army during the 1992-95 Bosnian war. He is held responsible for atrocities such as the massacre of 8,000 Muslims at Srebrenica as well as shelling and sniping during the Bosnian Serb siege of the capital, Sarajevo.