Lawmakers planned an emergency session to fill a power vacuum after the president's resignation, hoping to quell violent street protests by the country's poor Indian majority intent on wresting power from the wealthy white ruling class.
President Carlos Mesa (search), a U.S.-backed free-market supporter, survived only 19 months in office before offering to step down Monday, his government buckling in the face of weeks of protests by a coalition of Indians, miners and union members.
The resignation — expected to be put to a vote in Congress on Thursday — could ultimately usher in new elections, raising the prospect of Bolivia (search) becoming the seventh Latin American country to move to a leftist government opposed to U.S. policies in the region.
The crisis pits Indian and labor groups from the poorer eastern highlands, including the capital La Paz and its impoverished satellite city of El Alto, against the ruling class from Santa Cruz in the east and the oil-rich gas fields to the south.
Also at issue are the divides created by the U.S.-backed war on drugs: One popular opposition leader draws his support from farmers who grow coca-leaf, the raw ingredient for cocaine.
Mesa's offer to resign is expected to be accepted by Congress if it can convene an emergency session. Authorities said the session would be held in the historic formal capital of Sucre in southern Bolivia because of security concerns in La Paz.
On Tuesday, riot police in La Paz fired tear gas canisters and sent thousands of demonstrators fleeing down the cobblestoned streets of the old colonial center. Miners in brown hard hats responded by blasting dynamite sticks.
Ambulances sped away with the injured and a major public hospital said it had treated 12 people. Most had been felled by tear gas and rubber bullets, but the hospital said one miner lost a hand in a dynamite explosion.
A group of helmeted officers dragged miners out of the yellow dump trucks they had used to converge on the city, beating some of the protesters as others regrouped amid the biting tear gas that wafted over downtown La Paz for hours.
Urging Bolivians to "put an end to this craziness," Mesa went on national television late Tuesday to urge lawmakers to move quickly to call early elections for president, vice president and other posts, saying it was the only solution to the crisis.
Despite the resignation offer, opposition leaders have said they will not relent in the daily protests which, coupled with road blockades, have caused shortages of food, gasoline and water in the capital and shut down public transportation and most business activity.
During Tuesday's protests, thousands of anti-government demonstrators voiced their opposition to both of the congressional leaders in line to succeed Mesa: Senate President Hormando Vaca Diez, who is next in order of constitutional succession, and House leader Mario Cossio, who is second in line. Both hail from discredited traditional parties that Indian leaders have vowed to drive from office.
Vaca Diez said he expected Mesa to at least stay on until Congress decides on a political transition.
House deputy Evo Morales (search), who leads a leftist party whose power base is drawn from Indian coca-leaf farmers, warned that thousands of his supporters would move to prevent either Vaca Diez or Cossio from assuming the presidency.
"We will not allow them to take power. Now is when the national majority has to govern the country," Morales said.
A possible third-in-line, Eduardo Rodriguez, the president of the Supreme Court, enjoys wider political support and could serve as a caretaker president until early elections are held later this year.
Meanwhile, Washington has been watching Bolivia's unfolding political crisis with concern as Mesa's free-market policies have fallen out of favor after failing to ease the grinding poverty that affects nearly two-thirds of Bolivians.
Many in the poor Indian majority say they prefer a candidate from a non-traditional party like Morales, an avowed admirer of Venezuela's populist President Hugo Chavez (search) who has clashed frequently with Washington.
The anti-government protests have steadily increased since Bolivia's Congress last month raised taxes on foreign oil companies that have descended on the country to develop its natural gas reserves — the second largest in South America after Venezuela (search).
The tax increase touched off fresh demands for the nationalization of the oil industry and a new constitution giving more power to Aymara and Quechua Indians. Those two groups make up more than half the population.