• Rebels urged to avoid reprisals
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RACAK, Yugoslavia (CNN) -- Mortar and machine-gun fire Sunday drove international observers away from the scene of a massacre that took the lives of more than 40 ethnic Albanians in Serbia's rebellious Kosovo province.

Serbian police armored vehicles moved into the village of Racak, where the bodies of those slain in Friday's mass killings lay in a mosque. The shooting continued for at least half an hour.

"I consider this to be a very provocative act by the Yugoslav authorities, which have again broke the cease-fire," said Britain's Maj. Gen. John Drewienkiewicz, deputy head of the Organization for Security and Cooperation in Europe mission in Kosovo.

Drewienkiewicz said all the OSCE monitors were accounted for after the fighting, which comes as NATO ministers gather in Brussels Sunday to discuss the Kosovo situation. The conflict has escalated sharply in the last two weeks despite a three- month-old cease-fire brokered by the United States.

International monitors have accused Yugoslav forces of carrying out the massacre in southern Kosovo, where ethnic Albanians vastly outnumber Serbs. Some of the 45 bodies seen by U.S. diplomatic observers had eyes gouged out or heads smashed in.

The victims included a young woman and a 12-year-old boy. Many others were older men, including one 70-year-old. All the victims were dressed in civilian clothing, despite Serb police insistence that most of them wore uniforms of the rebel Kosovo Liberation Army (KLA).

The chief of the OSCE mission, William Walker, told a news conference Saturday that the massacre violated pledges made by Yugoslav President Slobodan Milosevic in October to avert threatened NATO air strikes.

Rebels urged to avoid reprisals

Walker said he has asked ethnic Albanian fighters of the KLA, which is fighting for independence for the province, to avoid any reprisals for "what can only be described as an unspeakable atrocity."

"As you might understand they have experienced anger, they have experienced frustration, all sorts of emotions," Walker said. "I have urged them to show restraint, and told them were they to seek revenge in any way, that I would equally condemn them."

U.S. President Bill Clinton, U.N. Secretary-General Kofi Annan and NATO Secretary-General Javier Solana all condemned the killings Saturday. The United Nations' chief war crimes prosecutor, Louise Arbour, will head a mission to Kosovo to investigate the massacre.

Senator urges NATO to put troops into area

Clinton blamed Serb security forces for the massacre, calling it "a deliberate and indiscriminate act of murder." Sen. John Warner, chairman of the U.S. Senate's Armed Services Committee, said the United States should take the lead in putting NATO troops into the area.

"If we leave that situation in Kosovo destabilized, it will undo what we have achieved, although modest, in the last three to four years in Bosnia," Warner said. "That situation will come unraveled; the billions of American tax dollars, the risk of our troops will be for naught."

U.S. Secretary of State Madeleine Albright conferred with fellow NATO foreign ministers, including those from Britain, France, Germany and Norway. She demanded that Milosevic bring those responsible to justice, State Department spokesman James Rubin said.

Rubin said Albright was demanding that Milosevic "identify who gave the orders and who took this action, and ensure that those perpetrators are then brought to justice."

The alliance in October authorized its forces to hit Yugoslav military targets if Belgrade violated pledges to seek a peaceful solution to the conflict with ethnic Albanian separatists. U.S. officials declined to discuss what options Washington would pursue at the NATO session.

Reuters contributed to this report.