BELGRADE, Yugoslavia (AP) _ NATO bombs set fuel depots across Yugoslavia ablaze today, lighting the Belgrade skyline and a town near the Hungarian border with the orange glow of burning fires. The United States apologized for an airstrike that damaged the Swiss ambassador's residence during a diplomatic reception.

A Yugoslav foreign ministry spokesman, meanwhile, denied U.S. and NATO reports of army desertions. Allied officials have cited the desertion accounts as evidence the NATO air campaign that began March 24 was working and raising the levels of internal unrest.

And little progress was reported in Moscow in talks late Thursday and early today between Russia's Balkans envoy, U.S. negotiator Strobe Talbott and Finland's president. Russia, which has cultural and religious ties to Serbia, opposes NATO airstrikes.

The state-run Tanjug news agency said one person was killed and several were injured when fuel storage tanks were hit by allied bombers in Sombor, a mostly Hungarian town 12 miles from the border with Hungary. Smoke billowed over Sombor before dawn today.

Also reportedly targeted late Thursday and early today were the Ostruznica and Lipovacka Suma regions near Belgrade, where more fuel depots and army installations are located.

The alliance bombed the Cukarica and Rakovica districts in the Yugoslav capital late Thursday. Serbian media said the Cukarica fuel depot, on a busy Belgrade street, was hit twice and set on fire.

Swiss diplomats confirmed their ambassador's residence was damaged in the strike, but said there were no injuries.

According to the Swedish newspaper Aftonbladet, Swedish Ambassador Mats Staffansson _ whose residence had been damaged in a bombing Wednesday night _ was among those at the reception Thursday.

``At a quarter past eight, we had just come to dessert, when a crash came. Four cruise missiles came down on a fuel depot only 300 yards from the Swiss residence. An enormous pressure-wave broke a very large picture window in the dining room. I, the Slovak ambassador and the Vatican ambassador threw ourselves under the dining-room table to get out of the way of the flying glass,'' the newspaper quoted him as saying.

In Bern, Switzerland, the U.S. ambassador to Switzerland, Madeleine Kunin, apologized to Swiss Foreign Minister Joseph Deiss. Neutral Switzerland, which is not a member of NATO, represents U.S. interests in Yugoslavia.

Foreign Ministry spokeswoman Monica Schmutz-Cattaneo said the Swiss made a formal diplomatic representation to both NATO and the United States, stressing that embassies should not be hit in future bombing campaigns.

The private Beta news agency also reported that the residence of the Indian ambassador was damaged by the strike on the fuel depot.

Deputy U.S. Secretary of State Talbott, Finnish President Martti Ahtisaari and Russian envoy Viktor Chernomyrdin wrapped up talks at a government resort outside Moscow early this morning.

Ahtisaari, who returned to Finland today, said the negotiations ``just keep getting better.''

There were still ``plenty of issues that are extremely difficult and the solutions for them don't necessarily please everyone, but maybe understanding will increase when there aren't many alternatives,'' Ahtisaari told reporters on arrival in Helsinki.

NATO wants the total and unconditional withdrawal of Milosevic's 40,000 troops and police in Kosovo, a return of all refugees and a well-armed, NATO-dominated international force to police the peace accord.

Talbott said the talks had been constructive and would continue.

On Thursday, NATO struck army barracks in Belgrade's plush Dedinje district where President Slobodan Milosevic lives and works. But one of the bombs went astray, leaving a hospital in smoldering ruins and three patients dead.

The Spanish, Indian, Norwegian and Hungarian ambassadors' residences were also damaged. Serbian media reported damage to Libya's embassy and the Israeli diplomatic mission.

There were new accounts of Serb soldiers deserting following U.S. reports that 500 have quit, mainly drafted soldiers from northern Kosovo.

A Yugoslav government official, Nebojsa Vujovic, denied today that soldiers who have returned from Kosovo this week to their homes in the central Serbian towns of Krusevac and Aleksandrovac were deserters.

``These reservists were regular soldiers returning home ... in accord with the army Supreme Command's decision to adjust army levels (in Kosovo) to peace time,'' Vujovic said.

``This is serious evidence that ... Yugoslavia is implementing this decision, but Western media interpreted these moves as desertions,'' Vujovic said. ``There are no desertions.''

About 5,000 residents of Cetinje _ almost one-third of the population _ today protested the recent Yugoslav army reinforcements around their city and to demand the military withdraw.

``We are here to ask loudly what these people in fatigues are doing in our city,'' Mirko Dapcevic told the crowd, his words followed by huge applause.

It was one of the first and certainly the biggest protest against the Yugoslav army in Montenegro, which, with much larger Serbia, makes up Yugoslavia. Montenegro's pro-Western government is at odds with Milosevic.

About 2,700 refugees crossed from Kosovo into Macedonia on Thursday, the highest number in several weeks, the United Nations refugee agency said today.

The refugees said areas around Pristina, Kosovo's provincial capital, had been ``cleaned out'' over recent days. Some also said ethnic Albanian men had to pay military and paramilitary forces to escape alive.

UNHCR estimates 800,000 people, the vast majority of them ethnic Albanians, have fled or been driven out of Kosovo since NATO began airstrikes. Most have gone to Albania. Kosovo had a prewar population of about 2.1 million people and in the 13 months before NATO intervened in March, about 2,000 were killed by Serb forces.