NATO STRIKING 24 HOURS A DAY; YUGOSLAV FORCES MAKE FINAL PUSH.

Byline: Veselin Toshkov Associated Press 

NATO blasted oil refineries, military barracks and airports in Kosovo, Montenegro and the Yugoslav capital on Friday, claiming one of the most successful nights in its nearly monthlong air campaign against Yugoslavia.

Air raid sirens sounded again late Friday in cities across Serbia. But reports of strikes were few, possibly because stormy weather hampered NATO pilots. Serb media said a factory in the central Serbian town of Valjevo was hit early Saturday, causing serious damage to the surrounding residential area.

In what may be a final push by Yugoslav forces to rid Kosovo of its ethnic Albanians, thousands of refugees were driven into Albania and Macedonia - with tens of thousands more on their heels.

At least 5,000 refugees crossed into Macedonia on Friday, and another 8,000 arrived in Albania by late afternoon. UNHCR spokesman Ron Redmont said an enormous flood of desperate people - upward of 100,000 new refugees - was believed bound for Macedonia alone.

Yugoslav President Slobodan Milosevic launched a crackdown on ethnic Albanian separatists 14 months ago in Kosovo, a conflict that has killed thousands and left tens of thousands homeless. NATO began bombing Yugoslavia on March 24 after he refused to sign a peace accord for the province.

Kosovo is a province in Serbia, which along with Montenegro makes up Yugoslavia.

A Yugoslav army officer captured by the rebel Kosovo Liberation Army inside Yugoslavia was delivered to American custody on Friday, the Pentagon said. The officer was captured earlier this week, delivered to the government of neighboring Albania, then to U.S. custody, the statement said. It was the first capture of a Yugoslav soldier since NATO began bombing.

Yugoslavian authorities are holding three American soldiers captured along the Macedonian border.

On the Yugoslav-Albanian border Friday, Albanian and Serb forces exchanged fire for five hours, Albania's Interior Ministry said.

The area has long been the scene of fighting between Yugoslav forces and the KLA, which uses northern Albania as a staging ground. But Albanian regular army troops have increasingly been drawn into the conflict - a development that ignites fears of a wider Balkan contagion.

Albanian officials said Serb forces ``tried to enter our territory'' near the northern hamlet of Bajram Curri, but were pushed back. No injuries were reported.

Shellfire was heard overnight Friday near Macedonia's Jazince crossing.

In Washington, State Department spokesman James P. Rubin said there is evidence of ``mass killings and graves associated with those mass killings'' in an area west of Pristina, the Kosovo capital. He had no information on the number killed but said it was more than a few dozen.

Rubin also said that, according to independent sources and refugee accounts, Serb forces damaged or destroyed over 400 villages and towns inside Kosovo, 45 of them in the last week to 10 days.

Yugoslav officials said 19 civilians were injured in the latest wave of NATO airstrikes. Serb authorities, who describe virtually all NATO attacks as being aimed at civilian areas, claim 500 civilians have been killed and more than 4,000 hurt in the bombing campaign. Those figures could not be independently confirmed.

On Friday, Yugoslavia declared a day of mourning for what it said were 75 people killed Wednesday when a refugee convoy in southwest Kosovo was hit in a strike it blamed on NATO.

A full picture of the convoy attack has not yet emerged, although NATO has acknowledged hitting one civilian vehicle. On Friday, the alliance again expressed regret over the loss of life, but said it was time to move on.

``NATO puts its setbacks behind it,'' NATO spokesman Jamie Shea told reporters. He said in the latest wave of attacks, the alliance hit targets all over the country and knocked out several tanks and artillery sites in Kosovo.

A German newspaper, meanwhile, reported that ethnic Albanian leader Ibrahim Rugova was being held under house arrest in Pristina. Rugova was brought to Belgrade, the Yugoslav capital, on Friday for a meeting with Serbian President Milan Milutinovic and Yugoslav Deputy Prime Minister Nikola Sajnovic.

Rugova did not appear before reporters afterward, but Yugoslav authorities issued a statement saying both sides had agreed that a halt to bombings was essential before any political settlement could be worked out.

The Red Cross, meanwhile, reported that an envoy was in Belgrade to discuss issues including the three American soldiers being held by Yugoslavia. However, spokesman Nick Sommer in Geneva said no quick breakthroughs were expected regarding the servicemen, who were captured March 31 while on reconnaissance along the Macedonian border.

The NATO airstrikes are now occurring around the clock. Slatina, the main Kosovo airport just outside the capital of Pristina, was hit Friday evening for the fifth time, the state-run Tanjug news agency said.

Also targeted in evening strikes were mounts Butovac and Goles, northeast and south of Pristina, Tanjug said. NATO has been targeting mountaintop transmitters. The Lipljan municipality south of the city was also hit, it said.

An earlier wave of attacks before dawn Friday targeted:

A military airfield and airport just outside Podgorica, the Montenegrin capital. Montenegro, Yugoslavia's smaller republic, has accused Belgrade of trying to draw NATO attacks against Serb targets in the pro-Western republic.

The southern Belgrade district of Rakovica, hit for a second consecutive night.

The country's largest oil refinery complex at Pancevo. Tanjug said it was hit three times.

A bridge over the Danube southeast of the capital.

Subotica, near the border with Hungary.

A settlement area of refugees from the wars in Bosnia and Croatia, in Paracin in central Serbia. Tanjug said no injuries were reported.

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Photo

PHOTO Ethnic Albanian children look out the window of a bus as they arrive at a NATO-run refugee camp.

Eric Draper/Associated Press