From the rim of the mountain chain forming the border with Macedonia it is possible to see distant evidence of the catastrophe. The sky bears red traces at night of forces on the horizon.
But the real evidence is the great suffering tide of humanity being driven forward remorselessly by the juggernaut. It is made up mostly of women, children and old people stripped of their money, valuables and papers. The numbers are becoming meaningless. In one pocket north of the border there are said to be 50,000; to the west there are perhaps 150,000 more.
The force that is driving them, which may be more than 100,000 strong, is spearheaded by tanks and artillery of the Serbian regular army but it now seems clear they are only the advance guard of something far more deadly, something that has not been seen in Europe for more than 50 years.
Descriptions of the Serb tactics are almost identical in each assault. It would be impossible to list the dozens of villages and hamlets that have been razed and their populations decanted into the fields and hills. But in the largest urban centres the evidence of massive "ethnic cleansing" is clear. We know the large town of Mitrovica in the north-west is deserted, a ghost town. The heart of the city of Pec has been burning for days and its entire ethnic Albanian population gone. Prizren, in the south-east, is almost a total ruin, its shops and homes looted and its entire male population missing. In Pristina, the capital, the Serbs have been more selective. Only the large Albanian neighbourhoods have been shelled, torched and turned to ruins.
From every one of these places the flow of refugees has been huge. So has the level of theft. Apart from their cash, valuables, passports and papers, there are an estimated 6,000 vehicles parked for miles north of the Macedonian border and now the property of the looting army.
The Serbs are using the rail system to make the flow faster, with trainloads of Albanians, loaded to the roof in Pristina and dumped - in the centre of newly sown minefields - miles from the border. An estimated 7,000 walked in a column stretching five miles yesterday. But the real mystery is the missing young men, intellectuals, teachers, doctors, lawyers, journalists and political leaders of every party. The guerrilla fighters of the KLA, who are getting reports out to Nato, say they have identified a mass grave with hundreds of bodies near Orahovac. In a river the bodies of 80 males have been seen.
This monstrous and efficient military machine, trained and controlled from Belgrade, must have been built up over months - even while President Milosevic's delegates were discussing peace in France. Its speed of movement, co- ordination and tactics are the work of preparation that speaks of long- held objectives and long-term political planning.
In each attack the technique is the same: frontal assault by heavy armoured units shelling from a distance, followed by fast armoured four-wheel-drive vehicles containing special-force units, followed by sinister and highly trained special-duties groups.
They have a bewildering number of acronyms. But their purpose is the same: to terrorise the population into paralysis, to weed out those whose names are on their lists, and to rob, rape and abuse the others into flight. The main specialist force is the MUP, a gendarmerie some 10,000 men. It controls the PJP, which has been responsible for more known atrocities than any other group. They call themselves police, but they are in effect mobile light infantry with mortars, machine-guns and armoured troop carriers. Commanded by a major-general, they are split into battalion-strength units.
In Pristina alone, the KLA says, there are 5,000 in the 24th Special Police Detachment, split into six groups. As back-up they have some 8,000 reservists.
Then, most dangerous of all, are the elite groups, such as the JSO, that form President Milosevic's bodyguard unit. There are only about 500 of them but they have been present - in small groups of 15 to 25 - at every atrocity. They have stylish black uniforms topped by red berets and their faces are always masked. The RDV, a kind of modern Gestapo, work in plainclothes.
They are responsible for the so-called "black" and "wet" operations - involving the seeking out of named individuals. They are the quiet men with the lists, but they are known to be experts in torture and killing.
And, inevitably - following the main action like vultures over an abattoir and specialising in looting, burning and the rape of young women - there are the thugs and criminals of the two main war-criminal gangs, controlled by Zeljko Raznjatovic, the man known as Arkan, and his rival, Franki Sonatavic.
The brutalities of these men have been seen in every war zone that has racked the former republic of Yugoslavia.
Arkan's men became notorious in Bosnia for gouging out the eyes of an old woman, and both men have been heavily involved in every criminal activity - from immigrant smuggling to drug-dealing - yet both enjoy the patronage of the top Serbian government officials.
Arkan, who has been seen recently in the Belgrade, denies his men are there.
But one witness, a journalist for German state radio called Valanita Saratini, watched as a group of men wearing the uniforms of the infamous Arkan Tigers took a young journalist from his office in Pristina and shot him in an alley.
They took away five other journalists from the city's main daily newspaper and they have not been seen again. Ms Saratini, who escaped after six days in hiding with her husband, a university lecturer, and their two children, gave a first-hand account of the "ethnic cleansing" techniques.
"First the tanks seal off areas of the city," she said. "I saw 30 tanks in one street. Then they just batter down the doors of homes, smash the windows of shops - taking anything, from liquor to jewellery, that takes their fancy - and drive the people out. But always there are the plainclothes men with their clipboards and they ask for the names. When one they have on their list is found they take him away. Then there is shooting. Then they go on to the next place."
Yesterday at the Macedonian border there was a new problem for the thousands arriving in the deep ravine they have to pass through. The Macedonian authorities, now alarmed to the point of national tension, have stopped processing them for hours at a stretch - leaving them without food or water, without toilet facilities or heating - while Serb police units push them forward from miles up the road.
From the hills overlooking the scene it looked like a rock- concert crowd. But there was no singing, just the crying of infants and the pleas of mothers begging for food.Reuse content