"Not a single body bears any sign of execution," Dr Sasa Dobricanin said. "The bodies were not massacred."

His comments came as Nato's two top generals revived warnings of strikes against Serb leader Slobodan Milosevic, who in turn vowed not to alter his policy towards Kosovo.

Mourning the loss of a husband and son

The killings in Racak have sparked an international outcry and calls for the case to be handed over to the international war crimes tribunal.

But Serb authorities have rejected an international investigation into the killings and barred Louise Arbour, the chief prosecutor of the UN war crimes tribunal, from entering the province.

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They have also ordered William Walker, the head of the international monitors, to leave Kosovo after he blamed police for executing at least 20 of the victims.

The Serb authorities say the victims, who include a woman and 12-year-old child, are separatist guerrillas who died in clashes after opening fire on police.

Walker 'mistaken'

Dr Dobricanin's team and colleagues from Belarus started the postmortem, which is being attended by international monitors, on Tuesday.

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Finnish forensic experts are expected to join them on Thursday.

The pathologist said the autopsy would probably take three to four days as it was ''going very, very slowly''.

However, he said it was already clear Mr Walker had been mistaken.

Dr Dobricanin has already said he suspects the bodies may have been mutilated posthumously to make it look as if they had been executed.

The corpses were taken to Pristina Forensic Medical Institute on Monday after two days of fighting between Yugoslav security forces and ethnic Albanian guerrillas, enraged by the killings.

Police removed the bodies from Racak's mosque despite demands that the case be handed over to the war crimes tribunal.

Dr Dobricanin told Serbian TV that the post mortem report and the examinations would be handed over to Pristina investigating judge Danica Marinkovic.