Protests against President Slobodan Milosevic flared for the third consecutive night last night when students defied a police crackdown to join demonstrators who were increasingly confident of toppling the Yugoslav President.
Opposition leaders vowed to unleash daily protests, strikes and mass civil disobedience as police reinforcements arrived in the town of Leskovac, 150 miles south of Belgrade, to quell a crowd chanting for the resignation of the government.
A key opposition leader was quoted yesterday as saying Serbs had "crossed the line" and were no longer afraid to oppose Mr Milosevic.
"A lot of anger has accumulated in the people, betrayed hopes, bad life", said Mr Goran Svilanovic, head of the opposition Civic Alliance, in remarks reported by the daily newspaper Blic.
Banners and posters denouncing Mr Milosevic sprouted across the nearby city of Nis, where thousands of residents queued to sign a petition for his removal. More than 20,000 signatures have been collected in the past few days in other cities, said the opposition.
Students from Nis University joined opposition activists despite threats of arrest from police, who tore down banners. One read: "There are many reasons why but we have only one request: that Slobodan Milosevic would leave".
In Leskovac the jailed protest organiser, Mr Ivan Novkovic (31), became a rallying point for demonstrators who clashed with police for the third night, shouting "We want Ivan".
Demobilised army reservists, whose protests over unpaid wages resumed when they blocked a main road in central Serbia, have started to join demonstrators.
Several protesters and police at Leskovac, traditionally rock-solid in support of the regime, were injured early yesterday morning when a crowd attacked the house of Mr Zivojin Stefanovic, the local head of Mr Milosevic's ruling Socialist party. Mr Stefanovic was restrained by police after threatening a protester with a pistol.
Tension continued to rise as both sides prepared for today's showdown at the town of Prokuplje, where the regime has decided to mass thousands of supporters at the same time as an illegal opposition rally.
Mr Vladan Batic, an opposition spokesman, said the government was trying to provoke a riot. "The gesture is the best sign of the deep agony of the ruling party", he said.
Mr Zoran Djindjic, leader of the Democratic party, warned that Mr Milosevic was in for a summer of discontent that would culminate in his removal from office. Labour unions and the Serb Orthodox Church have thrown their weight behind the campaign. The municipal council in Novi Sad, Serbia's second city, became the first to vote for Mr Milosevic to quit.
"We must extend these protests, to make them daily, to move Milosevic into resignation. Our message is: no future with Milosevic in power", said Mr Djindjic.
Despite the gathering momentum doubt remains over the ability of the Alliance for Change, an umbrella group of 30 opposition parties, to harness anger at NATO's bombing, the loss of Kosovo and the collapse of the economy.
There is also widespread revulsion at the treatment of Serb refugees from Kosovo, who as a political embarrassment have been hidden in remote holding centres and pressured to return home to an uncertain fate. Yesterday it emerged that the government ordered all primary and secondary school teachers not to enrol refugee children.