The umbrella group Alliance for Change, co-ordinating the protests, has announced that the demonstrations will take place daily in different towns across the country.
In the southern town of Leskovac, a former Milosevic stronghold, passions were running high because of the arrest of Ivan Novkovic, the television technician who - perhaps to his own surprise - has become a kind of revolutionary hero.
Mr Novkovic interrupted a commercial break during the broadcast of a basketball match on Monday night to air his own demands for the resignation of the local administrative boss, a Milosevic placeman. Crowds called for the release of Mr Novkovic, who has been sentenced to 30 days' jail for organising a rally "without previously informing the authorities".
His appeal brought 20,000 - more than one in eight of the local population - on to the streets. Protests have continued in Leskovac, and hostile crowds gathered round the home of Zivojin Stefanovic, the man whose resignation was top of Mr Novkovic's wish list. An opposition politician in the town, Vjacheslav Nesic, was taken into custody for several hours before being released yesterday evening. Mr Stefanovic had blamed Mr Nesic's brother, president of the local human rights committee, for the unrest.
There are rumblings of discontent across the country. In Novi Sad, north of Belgrade, the city administration has officially called for the resignation of Mr Milosevic. Signatures are being collected in Nis, Serbia's second city, calling for him to go. Trade unions are demanding that he step down.
The opposition parties have, in effect, been caught on the hop by the strength of feeling. Opposition party leaders are only now jumping on to the rebel bandwagon - unlike during the mass protest of winter 1996, when they played an important role in organising the demonstrations.
The rumblings are not yet explosive. If the regime sits tight, it could survive. Arrests may prove counter-productive and fuel popular anger.
The regime has also launched another favourite tactic, by scheduling a rally in support of President Milosevic at the same time and in the same place as an opposition rally due to be held in Prokupje, in southern Serbia, this evening.
On previous occasions, such clashing venues have been used as a way to stoke violence and thus increase people's fear of going out on the street. But the transparency of the tactic may only increase the indignation. Serbs do not like to be taken for cowards. Mr Milosevic may achieve the violence; but he is unlikely to force people to stay at home.
A more effective strategy is to block roads to prevent people reaching the towns where rallies are held.
Serb television news continues to paint a picture of a world where all is more or less rosy: the harvest is doing fine, and the United Nations peacekeeping force (the word Nato is never mentioned because it implies defeat) finds itself confronting Albanian terrorists in Kosovo.
Yesterday was a national holiday, marking the anniversary of the uprising of the Serb nation against Nazi invaders in 1941. The pro-government daily Politika carried a front-page headline quoting Mr Milosevic: "The struggle of our people against fascism was and remains a unique example of freedom- seeking and heroism, a beacon for future generations of defenders of the Fatherland".
The demonstrations are invisible in the official media. Instead, Politika talks calmly of the possibility that Serbia might join the European Union. Accuracy has never been the strong point of television news during Mr Milosevic's decade in power. Now, in the words of one opposition supporter in Belgrade, "the gap between the official version and reality is too great".Reuse content