Thousands Defy Ban by Kremlin : Soviet Union: Yeltsin’s backers rally in the center of Moscow, demanding Gorbachev’s ouster. Security is heavy, but a feared confrontation does not occur.

Tens of thousands of supporters of Boris N. Yeltsin, kept away from the Kremlin by 50,000 riot police and troops equipped with water cannon and horses, thronged central Moscow on Thursday to demand the ouster of Soviet President Mikhail S. Gorbachev and their hero’s election as Russian Federation president.

Defying a government ban on protests in the Soviet capital, the demonstrators--estimated by police at 100,000 and by organizers at half a million--rallied in the face of a law enforcement show of force so enormous and overt that it seemed designed to terrify them into staying home.

“We gather here, despite all the threats, to exercise the right of every Muscovite to freedom of speech,” reformist Mayor Gavriil K. Popov told the biggest rally, held at dusk on Mayakovksy Square about a mile from the Kremlin.

The heart of this city of 9 million, the official Tass news agency acknowledged, was transformed into something akin to “a city under siege.” Side streets were jammed with hundreds of army vehicles, dump trucks, flat-bed trucks or trucks carrying water cannon, waiting to be summoned to block access to the marchers or discharge riot police.

Ambulances stood ready near Red Square, and Tass reported that Moscow hospitals were placed on “red alert” to deal with the injured, but a feared confrontation never occurred. No injuries had been reported by the end of the day, and there were few arrests.

The pro-Yeltsin demonstration was timed to coincide with the opening in the Kremlin of an emergency session of the Russian Federation’s Congress of People’s Deputies. Yeltsin’s conservative foes had called for the special session, which would have the power to oust the 60-year-old chairman of Russia’s legislature--Gorbachev’s No. 1 political rival.

However, the threat to Yeltsin’s leadership appeared to diminish in the first hours of the Congress, which voted decisively to ignore the ban on all street protests in Moscow imposed by the Soviet Cabinet of Ministers.

Evidently fearing the consequences of a clash with supporters of Yeltsin, the country’s most popular politician, officials of the central Soviet government made it clear that they would not enforce to the letter the 20-day ban that went into effect Tuesday.

Interior Minister Boris K. Pugo said protesters would not be allowed to gather at the site of their choice--the plaza outside the Kremlin in front of the czarist-era riding school, the Manezh--but that police would not prevent rallies at Mayakovsky Square and another site half a mile from the Kremlin, Arbat Square.

Rally organizers from the progressive Democratic Russia bloc also chose to minimize the chances for what could have been Moscow’s first large-scale, politically motivated clash in Gorbachev’s six years in power by electing not to try to march to the Kremlin, the symbol as well as the seat of Soviet power.

At 5 p.m., several hundred protesters did try to set off from Arbat Square toward the Kremlin, but they were quickly blocked by 20 mounted police in white helmets, a platoon of Interior Ministry troops in flak jackets and more than 20 army trucks hastily parked in rows to block the street.

Earlier in the day, dozens of people chanting “Gorbachev resign!” and “Yeltsin! Yeltsin!” succeeded in pushing past metal crowd control barriers on Manezh Square but were repulsed by phalanxes of riot police carrying shields. Eyewitnesses said a handful of demonstrators were arrested. No other major clashes between police and the pro-Yeltsin forces were reported.

Most of the police seen on the streets carried long, black truncheons, but Pugo made the point that none of the police or his own Interior Ministry troops carried firearms.

Although the rally never came close to gathering the 1 million participants predicted by one Yeltsin loyalist, Mikhail Bocharov, speakers’ rhetoric highlighted the completeness of the break between Soviet radicals and the conservative and Communist Party forces with which Gorbachev is increasingly identified.

“The biggest violator and biggest criminal in the country today is President Gorbachev!” one pro-Yeltsin lawmaker, Leningrad police Capt. Yuri Luchinsky, told the crowd that packed Arbat Square.

“We must get rid of the (Communist) Party!” declared Nikolai Travkin, organizer of the rival Democratic Party of Russia. “If we just detach the tip of the iceberg, the party will return in an even more reactionary form.”

In a sudden snowfall, the protesters walked to Mayakovsky Square to join forces with people there. The esplanade surrounding the statue of Soviet poet Vladimir Mayakovsky became a sea of red, white and blue Russian banners and signs such as “Yeltsin: Thank You for Your Honesty and Courage!”

Many rallyers evinced a quiet resolve to do what is necessary to change the Soviet political system. “The police said they would take harsh measures, but all the same, people came,” said Dmitri N. Smirnov, 53, a Moscow teacher. “We’re tired of being afraid and of keeping our eyes closed to the truth.”

Yeltsin is expected to ask the Russian Congress to create a popularly elected Russian presidency, a post he has said he will run for and that he is virtually certain to win. Rally orators backed Yeltsin’s goal as a way to guarantee Russia--the largest Soviet republic--greater independence from the central government that Gorbachev has headed since 1985.

“We need to quickly hold an election for the president of Russia,” Popov declared, “or Russian law will remain just paper.”

Right-wingers said that if Yeltsin supporters were allowed to do what they wished on Moscow streets, it would be equivalent to mob rule. “If we permit the rally today, tomorrow demonstrators will be inside the Kremlin, and within a week they will be in this hall,” Air Force Col. Viktor I. Alksnis, a prominent member of the hard-line Soyuz faction, warned the Supreme Soviet, the national legislature.

Yeltsin supporters termed such apocalyptic rhetoric nonsense, since they have held rallies outside the Kremlin before that have assembled 100,000 people and more. The Moscow city government led by Popov had originally authorized Thursday’s rally.

Earlier Thursday, Gorbachev promised angry Russian lawmakers that although he would not accede to their request to lift the ban on demonstrations and call off his soldiers, he would remove the extra police, troops and military equipment from Moscow’s streets by today.

Yeltsin’s deputy, Ruslan I. Khasbulatov, who was dispatched to negotiate with the Soviet president in late morning amid mounting fears that violence would break out at the rally, told lawmakers that Gorbachev “showed his inflexibility and unwillingness to compromise” on the rally.

“Shame!” shouted some members of the 1,064-seat Congress, their voices echoing against the high ceilings of the Grand Kremlin Palace.

Russian lawmakers complained loudly throughout the Congress’ first day about the troop presence; some said that they felt “under siege” or imprisoned, and others remarked on how unpleasant it was to run a military gantlet to come to work in the Kremlin.

“Can you run a Congress behind the bayonets of soldiers?” asked a delegate from the Jewish Autonomous Region. “I consider it impossible.”

Liberals gained exactly the 532 votes they needed for a majority to pass a resolution invalidating the Soviet government ban on rallies and Gorbachev’s decree tightening his control on Moscow police. But because most Russian laws are technically subordinate to central Soviet laws, the move was considered largely symbolic.

In an initial discussion of the Russian Congress’ agenda, none of Yeltsin’s critics proposed a no-confidence vote, and few comments in general were directed against him.

Even several leaders of the Russian Communist Party, considered Yeltsin’s chief conservative opponents, skirted the issue of ousting him at an afternoon news conference, saying they wanted to concentrate on issues rather than personalities.

In Washington, Deputy White House Press Secretary Roman Popadiuk said the Bush Administration a day earlier had urged the Soviet government not to use force against the demonstrators.

Popadiuk said that U.S. Ambassador Jack F. Matlock Jr. raised the matter with Soviet officials on Wednesday in Moscow and that Secretary of State James A. Baker III delivered a similar message to the senior Soviet diplomat in Washington.

“We strongly urged the Soviet government to refrain from using force against peaceful demonstrators,” he said. “We also reminded the Soviet government of its commitments through the Helsinki process to respect the rights of peaceful assembly and demonstration.

“We urge the Soviet government to remove all unnecessary restrictions on rights of expression and assembly as soon as possible.”

Times staff writers Elizabeth Shogren in Moscow and James Gerstenzang in Washington contributed to this story.

Moscow Protest More than 100,000 people gathered along Tverskaya Street near Mayakovsky Square (1) and at Arbat Square (2). Riot police backed by water cannon and trucks blocked the protesters from reaching their intended rallying point in Manezh Square.(3)