CARACAS, Venezuela--In riots touched off by bus fare increases, Venezuelans sacked hundreds of stores, set vehicles ablaze and traded gunfire with police in the country's worst street violence in 30 years.

At least three people were reported killed and 326 injured in the rioting, which began when the new fares took effect Monday morning and spread to at least seven cities and towns.

The violence persisted into early yesterday in downtown Caracas, where sirens wailed as authorities put out fires and battled looters in streets filled with shattered glass.

Independent reports estimated damage nationwide to be in the millions of dollars. On some Caracas streets, virtually every store was looted.

"It is a popular uprising. There are riots everywhere. They are all furious," said Metropolitan Police Inspector Jose Lara Montilla, who commanded a police unit armed with shotguns in downtown Caracas.

Police were sometimes forced to retreat from efforts to quell the violence. There were no official tallies of arrests.

Perhaps the worst violence occurred in Guarenas, a shantytown about 12 miles from the capital where the disturbances began. People there formed human chains and threw rocks at National Guard troops in armored cars after the soldiers began firing birdshot and tear gas at looters.

In Guarenas, a 32-year-old pregnant woman who was not involved in the rioting was shot to death and at least 126 people were wounded, said journalist Igor Camacho of the Voz de Guarenas newspaper.

Rioters in the shantytown there emptied dozens of stores and supermarkets and set ablaze at least 14 vehicles.

The 50 percent increase in bus fares that sparked the protests is part of a reform package announced last week by the month-old government of President Carlos Andres Perez that aims to bring the oil-based economy out of recession.

Weak oil prices have struck a serious blow to the economy of this country that has for decades been one of South America's most stable democracies.

In the capital on Monday, two women were shot to death, one near the Central University of Caracas, the El Nacional newspaper said.

A police spokesperson said at least 140 people, including five police officers, were injured in Caracas.

In San Agustin del Sur and Catia, poor neighborhoods on the west side of the capital, the police "received a beating," a police commissioner said.

"This is getting ugly...The wellto-do neighborhoods in the east weren't affected today, but just wait until tomorrow," said the commissioner, who spoke on condition of anonymity.