Nato believes that one of the largest single expulsions of ethnic Albanians took place when the Yugoslav army turned its attention in the middle of April to Mitrovica.

Up to 100,000 people were forced to flee south from this industrial centre as troops targeted both Kosovo Liberation Army units and civilians.

Many of the civilians arrived in Albania on foot and in urgent need of medical treatment.

Refugees who fled Mitrovica have also provided testimony which supports allegations of atrocities in southern Kosovo. Many reported seeing roads littered with bodies. Rexhep Goxhuli, a refugee interviewed by the BBC's Panorama team in Albania, said "the road from Mitrovica makes you cry", adding that he had personally witnessed five killings.

But even more chilling are the so-far unconfirmed reports that Serb units spent the days leading up to the start of their military withdrawal disposing of bodies in mines at Trepca, north of the city.

One witness said that during the air strikes, Serb units brought bodies to the mines for cremation during the night. The allegations, some of which have come from KLA members, remain unverified.