MOSCOW -- Days of incendiary anti-NATO and anti-American rhetoric gave way to an unsuccessful grenade attack on the U.S. Embassy here yesterday afternoon.

Officials said they had no idea who was responsible, but several politicians tried later to moderate the harsh debate, warning that it was becoming self-destructive.

"The kind of rhetoric I've been hearing from the Communist Party and their allies leads to this," said Grigory A. Yavlinsky, a liberal member of the State Duma, parliament's lower house. NATO unquestionably was wrong to bomb Yugoslavia, he said, but Communists' talk of taking up arms to defend their Slavic brothers was only inflaming the situation.

At 1: 30 p.m. yesterday, a bright, sunny afternoon, a man dressed in camouflage and wearing a black mask got out of a sport utility vehicle across from the embassy and aimed a shoulder-fired grenade launcher.

When it didn't fire, he threw it down and pulled out another. The second failed as well. The man threw it down and jumped into the vehicle as police guarding the embassy opened fire. Two machine gun bursts from the sport utility hit the front of the embassy as the vehicle sped off.

Crowds of anti-American demonstrators outside the embassy ran screaming in fright. The attack was videotaped and shown on news programs.

No one was reported injured. The vehicle, a white Opel Frontera which reportedly had been stolen, was found not far away. Children playing nearby said two men ran from the vehicle.

In September 1995, a grenade was fired at the U.S. Embassy during a period of protest over NATO bombing of Bosnian Serbs. The grenade broke through a wall and damaged a photocopying machine.

After yesterday's incident, police pushed protesters to the other side of the street and stood shoulder to shoulder in front of the building, which is adjacent to Moscow's busy eight-lane ring road.

The Interior Ministry sent helmeted troops wearing flak jackets to reinforce the numerous police guarding the embassy.

The Foreign Ministry expressed regret, and President Boris N. Yeltsin issued a statement saying the attack "throws a shadow on Russia, which is currently undertaking titanic efforts to solve the crisis around Yugoslavia."

Angry protesters have gathered at the embassy since the NATO bombing started Tuesday, throwing eggs, ink and beer bottles. While demonstrators have protested at the embassies of NATO allies such as Britain, they have concentrated their venom on the United States.

Russian officials have provided plenty of poison. Humiliated by their nation's loss of power, they have accused the United States of manipulating NATO and trying to run the world as it sees fit, unchecked by international law or morality.

Over and over, Yugoslavia has been described as a land of fellow Slavs, who share the Russian Orthodox religion. Day after day, television reports from Yugoslavia show old men and young children, frightened and suffering, desperate for help from their Russian brothers. Similar pictures of the people of Kosovo, where Kosovar Albanians are being attacked by Yugoslav Serbs, are not shown.

Russian leaders have felt betrayed because NATO began bombing just after admitting Hungary, the Czech Republic and Poland -- once members of the Moscow-dominated Warsaw Pact -- despite Russian objections to the eastward expansion.

"The leaders of the alliance used so much pathos to convince us that NATO was an all-but-new organization that has disabused itself of the Cold War ills," Foreign Minister Igor Ivanov said last week. "However, hardly have they accepted three new members into their ranks when they have demonstrated their aggressive nature."

Ivanov went on to accuse the United States and NATO of introducing Islamic extremism to Europe by intervening on behalf of ethnic Albanian Muslims in Kosovo.

The first easing of the rhetoric appeared Saturday, when the Duma was considering a vote to break arms sanctions against Yugoslavia and send military assistance. The prospect of contributing to a large-scale war produced a more moderate Ivanov, who stopped calling the NATO bombing "genocide."

Even while asserting that the rebel Kosovo Liberation Army was preparing to provoke Yugoslavia with stepped-up "terrorist activities," Ivanov said Russia should not stoop to NATO's level and "allow ourselves to be drawn into an all-out confrontation, a new arms race and military clashes."

The Duma backed off approving military aid, while firing off volleys of angry rhetoric.

Last night, the widely watched news program "Itogi" began its weekly analysis of events with a report from its correspondent in Belgrade. The report showed Serbs gleefully tearing apart the wreckage of the American F-117A stealth fighter that went down Saturday and informed the Russian public of how thoroughly the Yugoslav authorities were searching for the pilot.

"They don't believe reports that the Americans rescued the pilot?" the surprised host asked. This in turn surprised the correspondent, who had no idea that NATO had reported the rescue the day before.

Then the host, Yevgeny Kis- elyov, showed some World War I footage, and a narrator suggested that in that war, Russia had brought terrible suffering upon itself by rushing perhaps too quickly to fight for Bosnian Serbs against Austria.

The unpopular war made Russia ripe for the Bolshevik Revolution and many years of anguish, the narrator said. Another clip showed a soccer game in 1952, in which Yugoslavia defeated Russia and Stalin called the Yugoslavs fascists.

This made Gennady A. Zyuganov, the Communist who was one of four parliamentary faction leaders appearing on the program, apoplectic. Kiselyov quickly scolded him, reminding Zyuganov that Stalin and his foreign minister had delivered fellow Polish Slavs to Hitler in the infamous Molotov pact in 1941 and that the Soviet Union sent tanks against fellow Slavs in Czechoslovakia in 1968.

Highly emotional images were still prominent last night. The Yugoslav ambassador, who is the brother of Yugoslavia's president, was given a long and deferential interview on another television channel.

And ultranationalist Vladimir V. Zhirinovsky, the bad boy of Russian politics, turned up on "Itogi" wearing a military uniform, vowing to recruit Russian volunteers to aid their Slavic brothers.

But it seemed as if reason were entering the debate as well.

Liberal politicians Yegor T. Gaidar, Boris Y. Nemtsov and Boris Fyodorov were interviewed on their way to Belgrade, where they hope to persuade Yugoslavia to come to terms with NATO.

And Kiselyov reminded Russians of just what kind of country they have.

"While there's so much talk of our Slav brothers," he said, "let's not forget we have a million Muslims who are brothers of the Kosovo Muslims."

Pub Date: 3/29/99