MOSCOW, JAN. 13 -- The Soviet army's weekend offensive in Lithuania may leave as casualties not only the people who got in its way, but the country's perestroika reform program, the "new world order" of closer superpower relations and even Mikhail Gorbachev's legacy as a democratic leader.

The bloodshed in Vilnius and the fear of additional military violence in Latvia, Estonia, Georgia, the Ukraine and other Soviet republics, come less than a month after Foreign Minister Eduard Shevardnadze astonished the world by resigning and warning of an imminent Soviet dictatorship. Now that blood has been spilled on the ancient streets of Vilnius, it appears that Shevardnadze was speaking from knowledge rather than emotion.

Although Gorbachev has escaped blame for incidents of violent repression in the past -- including the slaying by internal security troops of 19 civilians at a peaceful demonstration in Georgia two years ago -- he now faces furious questions from the mass democratic movement he played so great a role in creating: Did Gorbachev give the order for the Vilnius assault? If he did not, has Gorbachev become subject to the will of the army generals and the KGB security police?

"Both scenarios are tragic, but the second might be worse," said Janis Peters, a Latvian member of the Soviet legislature. "It would mean that Gorbachev has lost control of his own army, that he is a marionette. History shows that can only mean further destruction and violence."

In Tallinn, capital of Soviet Latvia, Russian leader Boris Yeltsin told reporters he had spoken by telephone with Gorbachev, and that the Soviet leader insisted he had not given the order for the Vilnius attack. Yeltsin also quoted Soviet Defense Minister Dmitri Yazov as saying that he had not issued the order either, but that one of the army commanders in Lithuania could have.

In some ways the killings in Vilnius are reminiscent of the Novocherkassk massacre in 1962, when Nikita Khrushchev, another Soviet leader who began his rule as a reformer, gave approval for troops to fire on factory workers in southern Russia who were holding a peaceful protest against price rises. Khrushchev subsequently failed to shift to a hard-line position fast enough to please the Communist Party apparatus, and he was ousted within two years and replaced by Leonid Brezhnev.

At a demonstration of about 5,000 people near Moscow's Red Square today, there were bitter voices shouting their rage at Gorbachev, crying that his hands are now "soaked in blood." These were voices that had once supported Gorbachev, voices that learned to speak freely only in the past few years. Now some of them were calling for his ouster. About the only thing the protesters could say in Gorbachev's favor was that a replacement could be even worse.

"This slaughter should end everyone's illusions about Gorbachev," said Alexander Podrabinek, a for-mer political prisoner who now edits the newspaper Express-Khronika. "Tanks, occupation, violence -- these are the tactics of the old regime, pure and simple."

The killings in Vilnius "are the work of a dictatorship of reactionary circles -- the generals, the KGB, the military-industrial complex and the Communist Party chiefs," said Yuri Afanasyev, a member of the legislature and a leader of the nationalist Democratic Russia movement. "And at the head of that party dictatorship stands the initiator of perestroika, Mikhail Sergeyevich Gorbachev."

The protesters, who marched from Red Square past the KGB building to Communist Party headquarters on Staraya Square, carried some of the most virulent anti-Gorbachev placards ever seen in this city: "Gorbachev Is the Saddam Hussein of the Baltics!" "Down With the Executioner!" "Gorbachev Is An Occupier!" "Down With Gorbachev the Bloody One!"

When troops using clubs and shovels and poison gas killed 19 nationalist demonstrators in Tbilisi, the capital of Soviet Georgia, in April 1989, the blame was pinned on key hard-liners in the leadership, including former KGB chief Viktor Chebrikov, who had been running the Kremlin while Gorbachev was abroad.

The conviction among many here that Gorbachev had no part in those killings was a kind of willing suspension of disbelief, intended somehow to serve the progress of reform.

But now that Gorbachev seems to have shifted over recent months toward the forces of hard-line reaction, declaring his intention to preserve the union at all costs, he is losing what little credibility he retained among members of the nationwide democracy movement.

He has weathered crisis after crisis, but it becomes harder every day to see how Gorbachev can survive politically when most people blame him and his reforms for leaving store shelves more barren than they ever were under Joseph Stalin or Brezhnev. Gorbachev already was fast losing the support of intellectuals, the middle class and others who benefited from his initial reforms, and the Vilnius killings may be the last straw for this segment of society.

It appears now that Gorbachev holds power for the same reason that earlier Soviet leaders held power: Because the military, the KGB and the Communist Party feel he is on their side. Len Karpinsky, a columnist with the newspaper Moscow News, said that while Gorbachev is not suited by character to be a dictator, the army, the party, the Russian Orthodox Church and the KGB have become dictators through Gorbachev.

The scope of the crisis reaches beyond the borders of the Soviet Union, and reformist leaders have argued that the crisis in the republics and the Kremlin is unfathomably dangerous for the country's relations with the West.

Shevardnadze predicted that if the bloodshed in Tbilisi -- or in Azerbaijan where Soviet troops intervened in ethnic warfare last year -- were repeated, the country could lose all it had gained in its new relationship with the United States and the rest of the world. Shevardnadze appears to have resigned with knowledge, at least in general, of what lay ahead.