They are made to transport bodies away from the sites of massacres and bury them. These groups are believed to be made up of Kosovo Liberation Army (KLA) members and other ethnic Albanian men who have been taken prisoner by the Serbs and forced to work under armed guard. Nato believes they are dressed in red overalls to make them easily identifiable to their guards. "This is further evidence of a concerted and organised campaign of murder and barbarism," a source said.
Yesterday Nato presented evidence of a newly discovered mass grave near the village of Izbica which is thought to contain 150 bodies. The site was photographed by a reconnaissance aircraft on Thursday, showing what looked like neat rows of graves in an area that was empty when a picture was last taken in March.
"There is now mounting evidence of detentions, summary executions and mass graves," said Jamie Shea, Nato spokesman. Refugees had reported incidents in at least 50 towns and villages in recent days. Two of these involved 45 Albanian Kosovars who were ambushed and killed, and another where 60 were murdered.
Adding the figures given by refugees together leads the alliance to believe that at least 3,200 people have been murdered inside Kosovo by Serbian forces in the past few weeks.
Robin Cook, the Foreign Secretary, will this week hand over a dossier of alleged war crimes to Louise Arbour, the chief prosecutor of the International Criminal Tribunal for Yugoslavia, who is coming for talks in London on Tuesday. The tribunal last week asked for help from all Nato governments.
Britain has compiled details of 87 incidents in breach of international law - including massacres, bombings and mass rapes - of ethnic Albanians in Kosovo.
Mr Cook will also publish the names of the six Serbian commanders whom the alliance believes have masterminded the atrocities in the Balkans.
The dossier, based on intelligence, information from the KLA and reports by refugees and the media, describes dozens of incidents which would, if proven, be classified as war crimes. It covers the period from 25 March to 14 April and details massacres of hundreds of people every day in villages around Kosovo. It also formally sets out allegations of Kosovan women being systematically raped at camps and in their homes by Serbian troops. Downing Street said it believed that all the information contained in the dossier was "verifiable".
The Foreign Office said it now had evidence of three more centres at which Kosovan women were being systematically raped by Serbians - on top of the training camp disclosed by Mr Cook last week. Refugees reported orchestrated rapes at Globocica, Urosevac and an unidentified point on the Kosovo-Albania border.
British intelligence has linked these atrocities to a small band of Serbian commanders, who have led the troops on ethnic cleansing raids in Kosovo.
Britain last week appointed David Gowan, a senior Foreign Office official, as Kosovo War Crimes Co-ordinator, responsible for compiling data.
Yesterday it emerged that Judge Gabrielle McDonald, President of the International Criminal Tribunal for Yugoslavia, had written to all Nato governments asking for their help. The judge's letter was quoted at the daily Ministry of Defence briefing.
"Many of these refugees recount experiences that, if true, belong in a place and time that we are supposed to have left behind," said the letter.Reuse content