Investigators found human body parts Wednesday at an alleged mass grave site in northwestern Macedonia, a police source said.
Macedonian authorities have insisted the site contains the bodies of missing Macedonian civilians who were executed by ethnic Albanian guerrillas. The rebels have denied all knowledge about the fate of the alleged victims.
Meanwhile, Macedonia's main moderate party walked out of the country's national unity government on Wednesday, in a move likely to make the implementation of a peace pact with ethnic Albanian guerrillas more difficult.
U.N. forensic experts, accompanied by NATO and European Union representatives, traveled Wednesday to the site where the government suspects 13 civilians missing since April were kidnapped, killed and buried in common graves by ethnic Albanian rebels who fought against government forces for six months before a tentative peace deal was reached in August.
The investigators, who began excavation of the site near the village of Trebos on Wednesday using mechanical diggers, reportedly had found body parts including bones buried around six feet deep.
"Our findings so far confirm information which we received from a witness about this location," the source said. "We assume there are six bodies in this place."
Controversy over the site has threatened to shatter the fragile Western-backed peace process which earlier this year pulled Macedonia back from the brink of civil war but has not yet taken a firm hold on the former Yugoslav republic.
Three Macedonian policemen were killed 10 days ago when special forces units were sent to secure the site located in territory held by the National Liberation Army guerrilla group until it formally disbanded in September as part of NATO-sponsored peace plans.
A small bomb exploded in the nearby mainly ethnic Albanian city of Tetovo on Tuesday night, local authorities said, in a sign of continuing tension in the area.
The bomb caused no injuries and little damage when it exploded near the European Union's office in the city. No one has claimed responsibility for the blast.
The international monitors were on hand at the site to prevent it from becoming the cause of new disputes.
In Skopje, Branko Crvenkovski, leader of the Social Democratic Alliance of Macedonia (SDSM), said his party saw no need to remain in government with its political opponents now a measure of stability had been re-established in the Balkan state.
"From today, the SDSM is no longer part of the broad coalition government," Crvenkovski told reporters. "Our ministers will resign and the party moves into opposition."
The unity government was formed in May, with the encouragement of Western powers.
Western diplomats fear the party's move will concentrate power in the hands of nationalists such as Prime Minister Ljubco Georgievski and Interior Minister Ljube Boskovski, who are seen as more eager for revenge than reconciliation with the rebels, who dsbanded in September.
"It's true that the international community has urged us to remain in the government," Crvenkovski said. "But we cannot act as babysitters for Georgievski and Boskovski and clean up their dirty work."
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