OAXACA, MEXICO — Thousands of federal riot police using tear gas and water cannons battled demonstrators in this once-picturesque state capital Sunday, prompting striking teachers and leftist groups to abandon the central square they had held for five months.
After hours of smoky clashes in the streets, the end of a political crisis that had left at least nine dead and tested President Vicente Fox came quietly.
With police halted at the edge of the central square, or Zocalo, late Sunday, demonstrators who had encamped there since May demanding the resignation of the state's governor started heading home.
"We've decided we're going to leave this space," said Daniel Reyes, a spokesman for the striking teachers.
But Reyes added that a march was planned for today, ending at the Zocalo.
"This is the heart and the house of the people," he said. "This is ours, and we'll take it back peacefully."
Protest leaders also said that a 15-year-old boy had been shot and killed, a report that could not be verified.
About 4,600 Federal Preventive Police officers moved into the sprawling city of 275,000 people about 230 miles southeast of Mexico City on Sunday morning after three people, including an American, were killed Friday.
With water cannons and riot shields, police dispersed protesters from behind barricades of rocks, tree trunks and sheet metal.
They were met with taunts, pleas, scoldings and the occasional hurled rock. Some demonstrators threw Molotov cocktails, triggering a return volley of tear gas.
Police then retreated to the edge of the Zocalo and waited for several hours before protesters started leaving about sundown.
Most of the resistance appeared to be peaceful. Many protesters stood face to face with the rows of incoming officers, chanting slogans. Others cut themselves with knives and syringes, smearing their blood on placards and the Mexican flag. Local websites reported about 50 arrests.
Protest leaders voiced anger at police tactics.
"The police came in fighting, as is their habit," Flavio Sosa, a leader of the protest coalition, the Popular Assembly of the People of Oaxaca, said in a radio interview.
The federal forces were dispatched over the weekend by Fox to end an increasingly ugly standoff between local government authorities and the union representing 70,000 striking public school teachers.
The dispute over better pay and working conditions had mushroomed into a larger political struggle as a loose coalition of trade unionists, indigenous groups, anarchists and leftist activists backed the teachers' call for Gov. Ulises Ruiz to resign.
Teachers union leader Enrique Rueda Pacheco said the protesters' demand for Ruiz's resignation was not negotiable.
"We don't agree with an operation of this nature they will resolve the conflict, because it's not going to resolve it," Rueda Pacheco said in a radio interview. "There are going to remain some wounds that this police operation isn't going to be able to wipe away."
The protesters accuse Ruiz of rigging the 2004 gubernatorial election, and more generally of maintaining the system of autocratic rule and patronage politics used by his Institutional Revolutionary Party, or PRI, during the 71 years it held a virtual monopoly on Mexican government.
Ruiz, speaking to local media Sunday, ruled out resignation.
Famous for its graceful colonial-era buildings and vibrant indigenous cuisine and art, the city of Oaxaca is now a trash-strewn, graffiti-covered combat zone that has seen its normally flourishing tourist trade fall drastically.
Fox's decision to send in federal police, after insisting for months the standoff was a local problem, caps a strategic battle to wrest control of the state capital without sparking a major altercation at a time of great political tension nationwide.
The country has been on edge for months after a disputed presidential election in July, escalating drug-related violence along the U.S. border and the Pacific coast, and a high-profile street brawl in May pitting federal and state police against residents of the town of San Salvador Atenco, near Mexico City.
A week ago, it seemed the conflict in Oaxaca might be at an end, after teachers tentatively agreed to return to work in exchange for a 30% raise over six years.
But the killing of American journalist Bradley Roland Will, 36, and two Mexican men Friday apparently prompted Fox to send in federal police, ostensibly to prevent further bloodshed.
Will, a photojournalist with an Internet-based alternative news agency, was shot in the abdomen while trying to conduct interviews at a street barricade.
Fox has been criticized by political opponents who charge that by not intervening sooner in Oaxaca, the federal government was seeking to placate Ruiz, because Fox's successor, President-elect Felipe Calderon, will need the support of the PRI to govern.
Fox's decision to send police to Oaxaca also goes against a long-standing reticence to use federal forces against protesters, after the government's brutal suppression of demonstrations in the 1960s and 1970s during the so-called dirty war sparked international condemnation.
The long-term aftermath for Fox and Calderon is unclear. The Zocalo, once filled with the tents of protesters, began to be covered again -- this time with the tarps of soldiers and police.
Enriquez reported from Oaxaca and Johnson from Mexico City. Times staff writer Carlos Martinez in Mexico City contributed to this report.