Belgrade, Rabi Al-Awwal 02, 1432 H/Feb 05, 2011, SPA -- Tens of thousands of Serbian opposition supporters gathered in Belgrade on Saturday to protest economic hardship, corruption and demand early elections from President Boris Tadic. The opposition bloc led by the nationalist Serbian Progressive Party (SNS) threatened to launch continuous protests if Tadic ignores the call for the polls. "We give them two months. If the bullies continue refusing to listen, then in April you will see me here, sitting on a piece of styrofoam," dpa quoted SNS president Tomislav Nikolic as telling the crowd. Nikolic's deputy, Aleksandar Vucic, said that if elections are not called within the deadline, the SNS would embark on a sit-in. "In two months we will come here in an even larger number, sit down and not move until we achieve our goal," he said. According to police, some 50,000 attended the protest in central Belgrade. That fell short of 70,000 the SNS - which organized free bus and train transports from all over the country - had anticipated. --SPA 19:34 LOCAL TIME 16:34 GMT www.spa.gov.sa/862200