Two police officers who had been searching for a protest leader were taken hostage Tuesday by demonstrators armed with machetes, the police chief said.

The officers were being held in the jail of the small town of San Bartolo Coyotepec, south of Oaxaca City, and the demonstrators planned to "exhibit" them later in the central plaza of the state capital of Oaxaca.

The hostage-taking was the latest sign of unrest in the southern state of Oaxaca, where protesters have besieged the picturesque capital since June, occasionally clashing with police.

The officers had been searching for protest leader Flavio Villavicencio earlier Tuesday, Police Chief Manuel Moreno said.

But the officers, Jose Luis Diaz and Joaquin Jimenez Ogarrio, told reporters that they were off duty Tuesday and were passing by Villavicencio's house when angry townspeople detained them.

And Villavicencio's wife, who was not identified, said the officers entered her house and pointed a gun at her and her children.

Police officials did not comment on any plans to rescue the officers. Federal officials have thus far refused to intervene.

The unrest began when state police attacked striking teachers who were pressing for a wage increase, and has since escalated to an occupation by thousands of teachers, unionists and leftists out in the historic central plaza. The protesters have repeatedly clashed with police, spray-painted buildings with revolutionary slogans, smashed hotel windows and erected makeshift barricades. Most businesses remain closed and police have pledged not to enter the plaza.

In addition to a raise, the teachers have pushed for the resignation of state Gov. Ulises Ruiz, whom they accuse of using force to repress dissent and of rigging the 2004 election to win office. Ruiz has denied the accusations and refuses to step down.

Also Tuesday, the Mexican Association of Newspaper Editors in a news release condemned the teachers' decision a day earlier to block the national Mexican television network Azteca and two daily Oaxacan newspapers from covering their events, due to the media outlets' alleged alliance with Ortiz.