The guerrillas have handed over the body to the OSCE, who are now transferring the victim to the Serb authorities.

The victim's brother is in good condition and has been released into the hands of the OSCE.

Peter Biles in Pristina: "Increasing fears of a possible new Serb offensive"

The news followed a build-up of Serb and Yugoslav security forces around the south-western town of Orahovac in an apparent effort to free the brothers.

Tensions have been increasing across the province as international mediators try to gather support for the interim peace agreement thrashed out in France last week.

Iliar Qerimi, 8, wearing a KLA uniform

Mediators were expected to meet ethnic Albanian leaders in the regional capital Pristina on Monday ahead of a resumption of talks in two weeks.

However, the ethnic Albanians have said the present climate of insecurity in Kosovo has made it impossible for them to consult their supporters on the plan for self-government.

Several attacks

On Sunday, peacekeeping officials reported that two monitors had been attacked by Serbian civilians.

The two members of the Kosovo Verification Mission were beaten up in the south-western town of Prizren, with one losing several teeth, B92 Yugoslav independent radio reported.

International monitors in Kosovo earlier said a Serb policeman was killed and four others wounded in an attack by ethnic Albanian guerrillas near the southern town of Kacanik, 15km north of the Macedonian border.

In a separate incident, one civilian was killed and two wounded in a shooting in the centre of Pristina.

The latest tension comes less than a week after Serbian and ethnic Albanian delegates ended 17 days of inconclusive peace talks in France.

Serb forces, under threat of Nato air strikes if they breach an October ceasefire agreement, have been steadily building up forces across Kosovo.

Following the fighting in Kacanik, international observers said the Serbs had prevented 2,000-3,000 civilians fleeing fighting to cross into Macedonia.

The KLA has marked a year of fighting

"There are people queued up along the highway about 500m short of the Macedonian border," UN spokesman Fernando del Mundo said.

"They want to cross into Macedonia as refugees but none of them have proper papers. The men say that if the women and children get across they will go back home."

In the Former Yugoslav Republic of Macedonia, the UN Protection Force Has ceased all activities because the UN Security Council failed to renew its mandate.