UN troops find Bosnia 'safe area' a shattered ghost town: Shelling inflicts 'humanitarian catastrophe of tremendous magnitude'

UNITED NATIONS troops who reached the Muslim enclave of Zepa in eastern Bosnia found a nearly deserted town, several bodies and 'a humanitarian catastrophe of tremendous magnitude'. The UN observers said thousands of inhabitants had taken to the hills after days of heavy Serbian shelling, leaving only a handful of people wandering the streets.

'Virtually every house is damaged and only about 50 persons are still in the town,' said Commander Barry Frewer, a UN spokesman. 'There had been heavy fighting, heavy shelling, and people have fled into the hills.'

The observers' report was the first independent confirmation of Muslim claims that Zepa, where there were 30,000 people, came under fierce Serbian shelling throughout last week. The observers arrived in the mountain village, 45 miles north-east of Sarajevo, late on Sunday afternoon after walking the last few miles because the road had been blocked by felled trees.

A statement from the UN Protection Force said 200 wounded needed to be evacuated by helicopter. 'Thirty of them need urgent attention.'

The observers reported that most residents had fled to the hills for safety. The people are living in huts, makeshift tents or out in the open and have been surviving on food from US air drops. The refugees urgently needed supplies, the UN reported.

Zepa was one of six 'safe areas' declared by the UN last week after Bosnian Serbs rejected the Vance-Owen peace plan.

Tension was also rising around another 'safe area', the town of Srebrenica, whose Muslim defenders last night received an ultimatum from the commander of Bosnian Serb forces, General Ratko Mladic. In a letter to UN peace-keepers, he warned he would be 'forced to take additional measures if the Muslims continued violating the agreement on demilitarisation of Srebrenica and Zepa, and cessation of hostilies in Bosnia.'

Under an agreement signed last month when the Serbs were on the verge of taking Srebrenica, the Muslims were to hand over their weapons to Canadian UN troops in exchange for a ceasefire in the region. Gen Mladic said the Muslims had failed to surrender their weapons when the deadline expired at 5pm yesterday.

In southern Bosnia, the city of Mostar was in flames last night after what UN military sources described as a well-planned Croatian attack. Bosnian Muslim military commanders said the Croatian army, the HV, rather than the Bosnian Croat militia (HVO), was involved.

Last night a ceasefire was declared in Mostar, but it seemed to have no effect. 'The few buildings left whole are burning. The destruction of the city continues,' Bosnian Muslim radio reported. Mostar remained closed to outsiders. Even the UN could not get in and a Spanish UN battalion, which withdrew an hour after the fighting erupted on Sunday night, was not able to return to the city.

The blazing Muslim quarter of Mostar lies west of the river Neretva. British soldiers said two precincts had been cleared of Muslims and there was evidence of extensive hand- to-hand fighting. Western television reports showed up to 1,000 Muslims being rounded up and marched out of the city by Croatian soldiers.

'It seems to have been a well- planned operation. Much of the equipment seems to have been moved in beforehand,' a spokesman of the British UN forces said.

The British army in Vitez could not say who started the fighting, but Lieutenant-Colonel Bob Stewart, who hands over command of the battalion today, said: 'It's a very serious punch-up with ethnic cleansing involved as well.'

WASHINGTON - The US ruled out military action in Bosnia before the weekend referendum by Bosnian Serbs on the Vance-Owen plan. 'Bosnia is in a holding period at this time,' Dee Dee Myers, the White House press secretary, said.