Separatists Shatter Georgian Truce : Black Sea: Abkhazians launch assault on the regional capital. Shevardnadze is unhurt when building is shelled.

Profiting from Georgia’s political chaos, Abkhazian separatists launched a major attack on the regional capital of Sukhumi on Thursday, shattering a 7-week-old U.N.-brokered peace accord.

Moscow immediately demanded that the rebels cease their “gross violation” of the July 27 cease-fire, arranged with help from U.N. and Russian observers. The commander of the Russian troops stationed in Georgia was ordered to stop the Abkhazian attack, the Interfax news agency reported.

At least 22 Georgians, some of them civilians, were killed and dozens of people were injured as about 700 Abkhazian troops stormed Sukhumi while others blew up a bridge near the village of Tamysh and shelled three villages in the Ochamchira region, Georgian officials said.

On Thursday evening, a firefight was being waged in downtown Sukhumi, the Abkhazian capital, where Georgian leader Eduard A. Shevardnadze had flown for emergency meetings.

The building in which Shevardnadze was meeting was hit by an Abkhazian shell, killing three people, Russia’s Itar-Tass news agency reported. Shevardnadze was not hurt.

A spokesman for the breakaway province said the offensive was not the result of official orders but a spontaneous “emotional outbreak” in response to Georgian breaches of the peace plan.

Georgians have prevented the Abkhazian government from moving into Sukhumi and have continued a 400-day blockade of the village of Tkvarcheli. On Thursday morning, they shot at unarmed residents who were trying to break through the siege, said Abkhazian government spokesman Kristian Bzhaniya.

“This aroused a storm of indignation throughout Abkhazia,” Bzhaniya said.

The 97,000 Abkhazians, a minority in their own homeland, began an armed revolt when Georgians tried to crush their independence movement a year ago. Sukhumi, once considered the most beautiful resort on the Black Sea, is now a bombed-out shell, and more than 2,000 people were killed before the July cease-fire.

Both sides withdrew from the war zone, and the peace appeared to hold until about three days ago, when the Abkhazians accused Georgia of hiding weapons inside the demilitarized zone and other violations.

Thursday’s offensive is another blow to the beleaguered Shevardnadze, who is now faced with three civil wars, widespread civil disorder and a crisis with Parliament.

Earlier this week, Shevardnadze stormed out of Parliament saying he was resigning, forcing lawmakers to give him sweeping emergency powers to crack down on an armed revolt in western Georgia by supporters of ousted President Zviad Gamsakhurdia.

Before flying to Sukhumi on Thursday, Shevardnadze sent a poignant telegram to Russian President Boris N. Yeltsin, saying the Georgians had abided by the terms of the cease-fire and withdrawn their weaponry from the war zone; thus they were now helpless to counter the Abkhazian betrayal.

“Now, we have nothing with which to defend ourselves, and there is nothing more I can do but fly to Sukhumi and together with its disarmed residents defend the city with my bare hands,” Shevardnadze wrote.

“These people, they have no conscience,” Col. Saba Baratashvili of the Georgian Defense Ministry said in a telephone interview from Tbilisi, Georgia’s capital. “Even if they take Sukhumi, are they ready to kill the entire population? I’m afraid that’s what they will have to do if they want to hold the city.”