Government supporters made several attempts to disrupt a rally of around 4,000 anti-Milosevic demonstrators in Prokuplje, 200km from Belgrade.

Scuffles broke out in the crowd and shots were fired. Protesters threw stones at a group of men who had hung an abusive banner from a building opposite the rally.

It was the first time the opposition coalition, the Alliance for Change, had successfully held a rally in a town normally associated with the government.

Brian Hanrahan in Prokuplje: "A taste of what will happen if rival groups gather"

A counter rally threatened by President Milosevic's Socialist Party failed to materialise.

Local party officials showed their nervousness when there was a sudden movement towards their headquarters.

The local boss came out with a gun and fired a volley of shots in the air.

There was more pushing and shoving, before the police moved in to protect the building.

The Alliance leaders believe that the rally has demonstrated the Socialists' weakness.

One of the opposition leaders, Zoran Djindjic, called for a referendum to be held on President Milosevic's future, AFP news agency reported.

He said nothing could justify the Nato bombings, but Mr Milosevic's regime had "come to the point where the choice has to be made".

He said the Serbian Orthodox Church had called for "a prominent government to be formed" and urged the need "for reforms and foreign economic assistance".

BBC's Brian Hanrahan: Anti-Milosevic feeling building up

The campaign against President Milosevic will continue with more demonstrations next week.

Mr Djindjic earlier went to Kosovo for meetings to try "to stem the flow of Serbs from Kosovo and to assure their return to their homes", an opposition statement said.

But members of Mr Djindjic's delegation received a hostile reception from local Serb villagers as they arrived for a meeting with church leaders at the Gracanica monastery near Pristina.

Serbian journalist Goran Gocic: Milosevic will fight to the death

Villagers accused them of abandoning them without food or aid since Yugoslav forces left Kosovo in June.

Some yelled: "Where were you a month ago?"

Mr Djindjic has been promoting a series of mass protests in Serbian towns and a petition - which has collected more than 100,000 - demanding that the federal Yugoslav parliament remove Mr Milosevic.

Mr Djindjic's Democratic Party is also submitting a motion in the Belgrade city assembly demanding Mr Milosevic resignation.

The municipal council of Novi Sad, Serbia's second biggest city, has already voted for Mr Milosevic to go.

The head of the Serbian Orthodox Church Patriach Pavle has already called for the president's resignation.

Momcilo Trajkovic: moved by meeting with Djindjic

On Tuesday, the Holy Synod started setting up its own anti-government council in Kosovo with local opposition leaders, as part of its efforts to persuade Serbs not to leave.

As the protests continue, the international Red Cross has warned governments not to overlook the humanitarian needs of Serbia and Montenegro while helping to rebuild Kosovo.

US President Bill Clinton and other leaders have pledged not to finance reconstruction in Serbia as long as President Milosevic is in power.

Serbs 'close to starvation'

The president of the International Federation of the Red Cross, Astrid Heiberg, has warned that many people in Serbia are on the verge of starvation because of the effects of the recent Nato air raids and international sanctions.

Dr Heiberg told the BBC that it was not only Serb refugees from Kosovo who were suffering, but also many elderly people on fixed incomes.

She was speaking in Belgrade at the end of a five-day visit to Serbia designed to highlight the situation.

Dr Heiberg also appealed to the international community to provide humanitarian aid to Serbia without conditions.

"We must fight the tendency to demonise entire groups of people," she said.

• Analysis: The battle in Serbia
• 'Refugees home by end of month'
• Serbian nationalists slam local media
• Zoran Djindjic: Serbian pragmatist
• Independent Serb media muted