Despite Peace Moves, Serbs Intensify Offensive on Two Fronts With PM-US-Yugoslavia, Bjt, and PM-Russia-Bosnia

SARAJEVO, Bosnia-Herzegovina (AP) _ Despite concessions to peace efforts in Bosnia, U.N. officials said today that Serb forces have intensified attacks on Muslim regions and denied permission for a relief convoy to travel to Maglaj.

Bosnian Serb artillery continue to hammer Maglaj, a Muslim enclave 50 miles north of Sarajevo, where 19,000 refugees have been under siege for most of the past year.

Serbs denied permission for a humanitarian aid convoy to travel there today, said Lt. Col. Bill Aikman, the U.N. spokesman in Sarajevo.

U.N. officials reported anti-tank rounds landed near Sarajevo's downtown Jewish cemetery this morning, but there was no word on who fired them.

There also were reports of a stepped-up offensive against Bihac in Bosnia's northwest corner, where Serbs support a small Muslim faction that has declared autonomy from the Sarajevo government.

The offensives contrast starkly to a truce that has held for three weeks in Serb-besieged Sarajevo, and to Tuesday's agreement by Bosnian Serb leader Radovan Karadzic to allow the reopening of an airport at Tuzla, northern Bosnia, for U.N. aid flights.

The Serbs attacks also come against the backdrop of agreement by Bosnia's Muslim and Croat factions to cease hostilities and form a confederation.

A preliminary accord was signed Tuesday in Washington by Bosnian Prime Minister Haris Silajdzic, Croatian Foreign Minister Mate Granic and Bosnian Croat representative Kresimir Zubak.

Rep. Susan Molinari, a New York Republican who chairs the House Bosnian Crisis Task Force, said the Croat-Muslim accord ''allows the world to collectively focus on Serbian aggression.''

Serbs now ''feel threatened'' and are ''launching an offensive in northern Bosnia, trying to take by force whatever they can, and quickly,'' said Neven Kulenovic, the charge d'affaires at the Bosnian Embassy in Zagreb, Croatia.

In Sarajevo, Aikman reported ''some gains'' by Serbs trying to cut a road and isolate the towns of Bihac and Cazin.

Serbs have signed a cooperation accord with a local Muslim leader, Fikret Abdic, who heads a self-proclaimed administration that broke from the Sarajevo government last year.

Aikman reported increased shelling of Muslim towns north of Sarajevo in recent days. Hardest hit appeared to be Maglaj.

Bosnian radio said Serbs fired 300 tank, howitzer and mortar rounds at the town early today, and that at least two people had been killed in the previous 24 hours.

The United Nations could not confirm the severity of the attack. U.N. plans to send an aid convoy to the town today where stymied when Serbs said no one with authority was available to grant permission.

Serb, Muslim and Croat leaders all have signed accords pledging free passage for aid convoys, but they have been ignored repeatedly, especially by local Serb commanders.

Maglaj depends almost entirely on airdropped aid, which is risky to retrieve from combat zones and often does not reach intended recipients. The town has had no land convoys since October.

Aikman said the Croat-Muslim truce that took effect Friday in central and southwestern Bosnia appeared to be holding, although there were some violations.

He said U.N. peacekeepers were setting up collection points for each side to turn in heavy weapons. The cease-fire accord calls for such weapons to be put under U.N. control or withdrawn from front lines by Monday.

Bosnian Croats and the Muslim-led government were allied at the start of the war. They have since fought each other for territory not claimed by Serbs, who control 70 percent of Bosnia.

More than 200,000 people have been killed in the conflict, which started 23 months ago.