Three Serbian policemen are missing, presumed dead, after In preparation for the European Union and Balkan heads of state summit meeting that was held yesterday in Zagreb, fighters from the Kosovo Albanian force, the Liberation Army of Presevo, Bujanovac and Medvedja (UCPBM), launched attacks on Serbian police forces throughout the demilitarized zone of Serbia along its border with Kosovo. But NATO has warned Serbia not to retaliate.
This area of southern Serbia is claimed by the Kosovo Albanians as Eastern Kosovo. The UCPBM, an offshoot of the KLA, operates out of Kosovo despite the presence of NATO forces. NATO is trying to throttle its activities, but this is a highly-mobile guerrilla force.
Strategically the small pocket in southern Serbia is very significant because the main arterial route from Serbia to Macedonia runs through it. On Thursday Serbian police were forced to re-route all border traffic because of guerrilla attacks.
From afar it might seem that the Zagreb summit of the EU and Balkan heads of state might be little more than a grand photo-op to celebrate the new democratic, pro-Western regimes which prevail in the two largest states of the region, Croatia and Yugoslavia.
But EU leaders are acutely aware that the peninsula remains ravaged and psychotic, teeming with potential conflict. The victory of the Serbian opposition is doubtless worth celebrating with vigour, but there is no room for complacency.
The priority lies in the stabilisation of Yugoslavia, the federation of Serbia and its tiny sister republic, Montenegro. For three years under their reformist president, Mr Milo Djukanovic, the Montenegrins have been steadily detaching themselves from Serbia.
Montenegro now has a separate currency and its leadership has demanded that it be recognised as a separate entity by the international community. Whether that means full independence is unclear.
This is especially worrying for the new Yugoslav president, Mr Vojislav Kostunica. His power as federal leader depends on the continuation of Yugoslavia. If Montenegro were to leave, he would have no political function.
In Serbia itself a power struggle between Mr Kostunica and his erstwhile ally, Mr Zoran Djindjic, is intensifying in advance of Serbian elections on December 23rd.
Mr Milosevic is exploiting the political confusion within the new leadership and the economic chaos in the country. This weekend his Socialist Party (SPS) is holding an extraordinary conference.
This was initially called to strip Mr Milosevic of his party functions. But he appears to have reasserted his control and could well lead the party into elections.
This explains the timing of the UCPBM's attacks in southern Serbia. Mr Kostunica's victory was not welcomed in most other parts of the former Yugoslavia. The Albanians of Kosovo, the Muslims of Bosnia, the Montenegrin leadership and even the Croats realised immediately that international attention would be diverted from their problems and political aspirations towards the much bigger question of Serbia.
As long as Mr Milosevic ruled Serbia the Kosovo Albanians, for example, felt they had a much greater chance of achieving independence.
France, currently holding the EU presidency, has organised the summit and dubbed it `the reunion summit,' a slightly unfortunate title given that representatives of several countries have spent the past decade in bloody attempts to escape union.
In particular, Croatia believes that it has earned a fast-track route to EU membership. Everybody agrees that the eventual solution to the problem of the Balkans is full integration into the EU. But in private most EU member states concede this process will take not years but decades.
The question for the EU is what to do about the Balkans between now and final acceptance into the organisation. Some analysts argue that the region should pursue internal integration in preparation for wholesale integration, while others suggest that the individual territories should compete against one another for membership.
Both strategies have apparently insuperable pitfalls.
But the incentive for the EU to devise a real set of policies for the region is considerable. Despite the impressive victory of democratic forces in several Balkan states, large parts are still in the thrall of deadly mafia operations.
These specialise in drug-running, gun-running, prostitution and cigarette smuggling on a vast scale. But above all the Balkans are the favoured route for the organisers of illegal immigration into EU states from Eastern Europe and Asia.
As a consequence the Balkans remain the single greatest security problem for the European Union. At any one time NATO has a quarter of a million troops wrapped up in the Balkan imbroglio.
So although the downfall of Mr Milosevic represents probably the most encouraging sign in the region over the past decade, the real work has only just started. If the EU gets its policy wrong, we could still be in big trouble.