A coalition of businessmen and civic groups Monday began an indefinite general strike aimed at toppling Gen. Manuel Antonio Noriega by completely shutting down the already crippled economy.

The streets were calm early Monday with the start of the strike. Heavily armed combat troops and riot police equipped with shotguns and tear-gas launchers patrolled the streets of the capital.The government said a special police security operation is in effect Monday across Panama City to guard shops that were open in defiance of the strike call.

The opposition Civic Crusade a coalition of business, professional and civic groups called the indefinite general strike after the government declared a "state of urgency" Friday because of

what it called the U.S. "undeclared war" against Panama's economy.

More than $50 million in Panamanian assets and payments for the Panama Canal have been frozen in the United States, creating a severe cash shortage and banking crisis.

"We are really hurting from the economic crisis but we hope this will be the last strike and we will get rid of Noriega," said a shopkeeper standing outside his closed shop on Via Espana, a popular middle-class shopping avenue. The government warned all state employees that they faced suspension or dismissal if they joined the strike, and most public utilities and government ministries appeared to be working normally.

Panamanians prepared for the strike by stocking up on food and other essentials. Opposition leaders said the stoppage would paralyze the country's economy and would continue until Noriega steps down.

In Washington Monday, Juan Sosa, Panama's ambassador to the United States, said on NBC's "Today," "I think his (Noriega's) days are numbered."

"His options are out and he has to leave Panama," Sosa said. "(Noriega) cannot imposed his terms on any solution."

Sosa supports ousted civilian President Eric Arturo Delvalle, who was removed from office last month a day after he tried to fire Noriega because of U.S. drug trafficking indictments against the military strongman.

A senior air force pilot who defected from the Panamanian Defense Forces after participating in last week's failed coup against Noriega said Sunday that his nation's de facto ruler had secretly stockpiled tons of Cuban-supplied weapons.

Maj. Augusto Villalaz said on ABC's "This Week with David Brinkley" that he had flown three planeloads of Cuban weapons to Panama in recent weeks. Villalaz said Noriega had hidden Cuban rifles and ammunition around the country for use in possible guerrilla action.

He said Noriega ordered 16 flights to bring in some 500,000 pounds of arms. Sources in Panama have told United Press International Noriega brought in at least one 16-ton load of Cuban rifles and ammunition.

Noriega has imprisoned about a dozen officers linked to the coup attempt and reportedly forced 20 to 30 others into retirement or exile. The sources said the purge created distrust in the military and predicted another uprising "very soon" if the country's crisis continues.

Secretary of State George Shultz told NBC's "Meet the Press" Sunday that Noriega should go into exile in Spain, which has offered him asylum, before the opportunity disappears. He declined to say what would happen if Noriega refused.