At a ceremony marking the anniversary of the medieval Battle of Kosovo, Patriarch Pavle said the president was to blame for the current situation in the province.

He called for urgent action from the United Nations to ensure the survival of the Serb people, who are leaving Kosovo in droves, fearing revenge attacks by Kosovo Albanians.

The volatile situation was highlighted by reports of two explosions on Monday night in the provincial capital Pristina.

The BBC's Jeremy Bowen: "If one man is to blame, it is Milosevic"

A powerful blast was heard near a former Yugoslav army barracks just outside the city. Another explosion followed shortly afterwards.

British soldiers from the Kosovo peacekeeping force, K-For, immediately headed for the area. Reports also said burning houses could be seen inside the city.

Serb fears

The patriarch's condemnation came as the first Kosovo Albanian refugees to be repatriated under UN auspices arrived in Pristina.

Many refugees have already returned without UN help.

The influx has provoked panic among Serbs as stories of killings, kidnappings, and the torching of homes by Kosovo Albanians multiply.

Paul Wood reports: "The Orthodox church always seemed to walk hand in hand with Serbian nationalism"

Fears of violence led to the battle anniversary - known as St Vitus Day - being marked in a more low-key ceremony than usual.

In Belgrade, a group of 50 Serbian intellectuals called on Mr Milosevic to resign in view of what they called the "final defeat of national interests and the countless graves of innocent Serbs".

Father Sava denounced Mr Milosevic

Another church leader, Father Sava, said Mr Milosevic had "brought ruin on the Serb people".

"The Milosevic regime does not support the Christian values we are fighting for and want to preserve," he said.

The Orthodox church commands great respect in Yugoslavia, and in recent years there has been a growing rift between the clergy and the president.

A BBC correspondent in Kosovo, Paul Wood, says Serbs will only hear about the church attacks through the veil of a heavily censored state media.

Refugees escorted back

As the ceremonies got under way, 10 buses, carrying nearly 400 Kosovo Albanian refugees from the Stankovic camp in Macedonia, drove into the regional capital, Pristina.

Refugees cheered as they crossed the border into the province but these turned to cries of dismay as they saw houses that had been wrecked or burnt during the conflict.

The UN repatriation programme comes two weeks after Kosovo refugees began to stream back across the borders of their own accord. About 416,000 have already returned.

The UNHCR will now be running a regular shuttle service to the province for the remaining 342,000 refugees.

But the refugee organisation is laying on buses to only three towns which have been declared safe by Nato.

(Click here to see a map showing refugee movements)

The agency is planning to provide the refugees with monthly rations until life can return to normal.

Representatives from the Mother Theresa Society are also on hand in the provincial capital to provide support to the new arrivals.

KLA disarm

In another development, hundreds of Kosovo Liberation Army (KLA) fighters have been handing in their weapons and moving into special assembly points across Kosovo.

Under an agreement signed last week the KLA has until midnight on Monday to take its soldiers and weapons off the streets.

The Supreme Commander of Nato forces, General Wesley Clark, told the BBC that KLA commanders were co-operating well on demilitarisation.

But he said he was concerned about how individual members would behave, given the anger among Kosovo Albanians.

The agreement gives the KLA 90 days to disarm completely. Most of their weaponry is to be kept in storage places supervised by the international peacekeeping force.

Impartial system

The first tentative steps towards creating a new civil administration have also been taken.

The UN's special representative in Kosovo, Sergio de Mello, swore in seven legal experts who will help select judges and create a new, impartial, multi-ethnic judicial system.

The experts consist of members of the international community, Kosovo Albanians and a Serb.

At the same time an advance contingent of UN international police has arrived from Bosnia.

Some 3,000 UN civilian police will be based in Kosovo, and eventually they hope to create and train a local police force.

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