MANAGUA, NICARAGUA, JULY 9 -- A week-old general strike backed by the opposition Sandinista Front against the new government of President Violeta Chamorro turned violent today, transforming the streets of this capital into scenes of chaos.

Workers, students and teenagers loyal to the Sandinistas exchanged volleys of rocks with Chamorro's supporters and gunfire punctuated the clashes. The police, many of whom remain loyal to the Sandinistas, at first appeared unwilling or unable to control the Sandinista mobs manning scores of barricades. Late this afternoon, however, police began clearing the streets, in some cases with bulldozers.

As darkness fell, Sandinistas were in the streets rebuilding the dismantled barricades.

The Sandinistas briefly seized control of one of the two state-owned television stations as well as Radio Nicaragua.

Hospitals confirmed four deaths and 54 persons injured.

Reporters saw both Sandinista militants and pro-government bands armed with AK-47 assault rifles. Sandinistas said that pro-government mobs had fired on them but this could not be independently verified.

The violence confronted Chamorro with the most severe crisis of her 10-week-old administration and appeared aimed at compromising political and economic policies she has put forth to move Nicaragua away from the socialist rule of the Sandinistas she defeated electorally.

Tonight, in a three-minute speech on radio, Chamorro asked that Nicaraguans "not respond to violence with violence." She proposed a "broad national dialogue involving all sectors" but said it "must occur in a climate of peace and understanding." The president said she had ordered the army and police to clear the barricades and retake occupied government offices.

Although there were reports that barricades had been erected in some provincial cities, the violence seemed limited to the capital and did not appear to amount to an immediate threat to Chamorro's government, which took office April 25.

Nonetheless, the breakdown in civil authority halted virtually all commerce and government business. Overnight and early this morning, Sandinistas ripped up pavement stones from the streets, passing them hand-to-hand to erect five-foot barricades on every major thoroughfare.

Vehicles that attempted to dodge the barricades were stopped and, in some cases, battered by the Sandinista mobs. One car that tried to negotiate around a barricade in the eastern neighborhood of Rubenia was set upon by the Sandinistas, who smashed its windows as two women in the back seat screamed in fright.

Also in Rubenia, a pitched rock-throwing battle broke out when a pro-government mob attempted to dismantle a barricade erected by the Sandinistas. A half-dozen policemen in riot gear tried briefly to intervene but appeared overwhelmed by the hundreds of people, most of them teenage and younger males, who surged through the streets.

At intersections throughout the city, residents choked on acrid black smoke from piles of burning tires. Smoldering tires and street barricades were enduring images of the 1979 revolution that brought the Sandinista guerrillas to power.

Passions were inflamed by local radio stations loyal to each side. Pro-government stations attacked the Sandinistas as anarchists while pro-Sandinista stations exhorted their partisans to man the barricades.

A communique from the Ministry of Government reminded citizens that the strike had been declared illegal last week and that anyone involved in it could be imprisoned for six months to two years.

Former president Daniel Ortega, who was defeated by Chamorro in February, made a radio address appealing for calm and blaming the violence on the government's policies and threats over the weekend to use force to end the strike. He called for a negotiated solution.

Immediately after the election, Ortega vowed that the Sandinistas would continue "governing from below" in order to "protect the conquests of the Sandinista revolution." Today, at dozens of barricades around the city, Sandinista stalwarts echoed that vow. "Not one step back!" they chanted. "Free fatherland or death!"

A previous strike mounted by unions loyal to the Sandinistas in May shut government offices and won a 100 percent wage increase for government workers. However, it was ended by negotiations with the government and did not result in violence.

The current labor action, which began last Monday, has escalated steadily, stopping work in government offices and state-run industries and interrupting banking, electrical, mail, telephone and other services.

The strikers are led by the pro-Sandinista National Workers' Front, which said 90,000 government workers had walked off their jobs to protest the Chamorro government's policies.

The strikers have asked for steep pay increases and job security for government workers as well as a number of political measures. They have demanded that the government protect peasant land distributed under Sandinista land-reform programs. Chamorro has said some confiscated land will be returned to previous owners.

The government has said it wants to trim the size of the government and reduce the fiscal deficit to stem inflation, which by some estimates is running at more than 100 percent a month.

On Friday, the government announced a 43 percent wage increase for civil servants in lower pay brackets, as well as cost-of-living adjustments for about 65,000 of the government work force of 100,000. But strike leaders rejected the offer as a pittance in the face of soaring prices.