Teachers enraged by the shooting death of a colleague seized government offices and blocked roads Tuesday in southern Oaxaca state, the site of months of violent demonstrations by teachers three years ago.
Leftist groups that battled with authorities in this picturesque Mexican colonial city for five months in 2006 are working with the educators in this latest strike, using hijacked trucks and buses to block intersections.
Protesters with loudspeakers vowed to paralyze the city.
The unrest was sparked by Thursday's shooting of teacher Antonio Norberto Camacho during a union clash at a bilingual elementary school.
Angry colleagues immediately began organizing protests, and by
Tuesday, teachers and their supporters were taking over dozens of
public offices including courts, prosecutors and civil service centers.
Teachers in one union - known as Section 22 - said that 13,000 schools serving 1.3 million students would be closed through Sept.
4 as they demanded a fair investigation into the shooting. They also called for the ouster of a different union - Section 59 - that is currently running more than 150 schools in the region.
Azael Chepi Santiago, secretary of the Section 22 teacher's union, said the strikes were their only way of pressuring state authorities.
"We didn't want to generate more conflict this year," he said, but the shooting "leaves us no alternative."
Jorge Toledo, the interior secretary for the state government, urged the protesters to seek "dialogue and consensus." He said the investigation into Camacho's killing has advanced and authorities "expect to detained those responsible very soon," according to a statement.
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