The Bosnia Crisis: Pockets of confusion blur military facts and factions: The Balkan Factor

THEY call it 'the Balkan factor' - the logic-defying tangle of local alliances and feuds which makes attempts to comprehend the Bosnian war a nightmare for outsiders. Compared with the overall confusion, the complex issues involved in attempts to end the siege of Sarajevo seem relatively comprehensible.

Muslims paying Serbs to bombard Croats; Croats paying Serbs to bombard Muslims; and breakaway brigades of Muslims colluding with Serbs against the main Muslim force. The permutations in defining the battle lines seem endless.

Starting in the south, the old hatred between Croat (Ustashe) and Serb (Chetnik) in Herzegovina is as intense as ever. The Muslim-led Bosnian Army (BiH), holed up in east Mostar under Croat bombardment, occasionally pay the Serbs 1,000 Deutschmarks ( pounds 400) a shell to bombard the Croats.

Yet in central Bosnia, the Croats pay the Serbs - yes, you've guessed - DM 1,000 a shell to bombard the Muslims in Zenica.

The Croats and Muslims are fighting a murderous, if static, war in central Bosnia, and the Croats and Serbs, although keeping a wary eye on each other, are co-operating.

There are two large Croat pockets in the Muslim heartland of central Bosnia, Vitez and Kiseljak, and two tiny ones, Dostansko and one south-west of Konjic. The Vitez pocket is isolated and has held off the BiH for months. The Kiseljak pocket abuts Serb-held territory and there is now a supply route from the solidly Croat area - the 'mini-state' of Herzeg-Bosna - through Stolac and round through Bosnian Serb territory into the Kiseljak pocket. It has been used to supply fuel, the Serbs extracting a fee for their co-operation by diverting some of the fuel trucks.

Then it starts getting a little complicated. First, there is Maglaj pocket, in the north of which the BiH and the Bosnian Croat HVO are co-operating against the Serbs. But in the south of the pocket, the BiH are hemmed in by the HVO. The HVO here are operating in collusion with the Serbs and fighting the BiH in the south of the pocket and in the main Muslim area to the south.

Further to the north, around Tuzla, the BiH and HVO are squarely allied against the Serbs, and fighting together to try to cut the Posavina corridor near Brcko, which links the two lobes of the Bosnian Serb-held area.

Finally, there is the Muslim pocket of Bihac, surrounded by Serbs. But in the north, two 'brigades' of the BiH V Corps have broken away from the main body of V Corps. There is some evidence they are paying the Serbs to shell V Corps or, at least, are colluding with them.

The Bosnian civil war battle lines have remained fairly static for months. The Serbs and Croats seem content to hold their present positions across the majority of the country, shelling certain targets and with occasional limited and specific forays. The Serbs seem most content and, until this week, there was no evidence of large- scale activity on their part.

The Croats are determined to hold their present border in central Bosnia and Herzegovina, though they would like to push the confrontation line with the Muslims east, away from Prozor, and to have all of Mostar as their capital.

The Croats would also like to relieve the Vitez and Kiseljak pockets, but have insufficient manpower to do so. The BiH still want to take them, and reckon that, although there are about 11,000 Croat HVO troops, only about 200 extremists are really determined to keep the Vitez pocket independent of the Bosnian command. The rest would probably be happy to live alongside their former neighbours. However, seizing the pocket would be an enormous task for the BiH.

The most obvious objective for the BiH would be to link up with encircled Sarajevo. But, realistically, the Serbs around Sarajevo are too strong and the Bosnian government army knows it. Their better bet is to rely on the UN to disarm, administer and feed Sarajevo, something which this week's events turn into a possibility.

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