Serbs retaliate with undeclared war against UN observers

BOSNIAN Serb authorities put United Nations personnel under virtual house arrest yesterday in apparent retaliation for Nato's air strikes against Serbian forces. They also threatened to charge a team of foreign aid workers with arms smuggling.

The UN and the Bosnian Serbs were close to undeclared war as General Ratko Mladic, the Bosnian Serb commander, said that his forces would shoot down planes flying near their positions.

The Serbian response to Nato's attacks in the Gorazde enclave on Sunday and Monday included laying mines around UN weapon collection sites in Sarajevo, preventing UN vehicles from driving through Serbian checkpoints, and ordering about 40 UN military observers in Serb-held areas not to leave home. The chief UN observer, Roy Thomas, said sentries had taken up guard outside the homes of some of his staff: 'They have not been harmed, just confined.'

In a sign of mounting pressure on Westerners in Serb-controlled zones, Bosnian Serb security officers said they planned to put on trial 11 French charity workers arrested last Saturday while travelling to Sarajevo from the Adriatic port of Split. The Serbs say the team was trying to smuggle ammunition into Sarajevo for the Muslim- led government, an allegation French authorities denounced as a lie.

The 11, who include a 25-year-old female logistics expert, work for Premiere Urgence, a charity that co-operates in Bosnia with the UN High Commissioner for Refugees. Belgrade television said they were in prison in Lukavica, a Serb-held Sarajevo suburb. The charity's spokesman, Thierry Mauricet, said Serbs had planted the heavy machine-gun ammunition in vehicles and the smuggling charge was nonsense. 'This is a cover-up for sheer hostage-taking,' he said.

The UN was also concerned about the fate of a Dutch military observer and his interpreter who went missing on Monday outside the Serb-surrounded Muslim enclave of Zepa in eastern Bosnia. UN officials said they had sent two letters to the Bosnian Serb armed forces but had had no reply.

Some Western governments have long been worried that Nato strikes against Bosnian Serb targets might jeopardise UN personnel and private aid workers. A similar situation arose in Iraq in 1990 when Saddam Hussein held dozens of Westerners temporary hostage to deter the US-led operation to recapture Kuwait.

To follow up its air strikes, Nato is considering an ultimatum to Bosnian Serb forces to withdraw from positions around Gorazde or face more attacks. But the Western use of force has already provoked a hostile Russian reaction that threatens to have implications for the whole spectrum of East-West relations.

President Boris Yeltsin, angry that Nato attacked the Bosnian Serbs without consulting him, suggested in Spain yesterday that Moscow might refuse to sign Nato's Partnership for Peace initiative 'when Russia is permanently discriminated against'. Russia is supposed to join the programme in Brussels on 21 April.

Serbian and Muslim forces clashed yesterday around Gorazde. The UN commander, Lieutenant-General Sir Michael Rose, said Muslim forces were firing mortars at silent Serbian positions. However, other UN officials said later that the Muslims had come under fire from Serbs.

Extra troops line up for Gorazde, page 9

Letters, page 17