Mexican officials have announced plans to dispatch troops, marines and federal police forces to the nation’s southern states to protect polling places as violence threatens midterm elections over the weekend.

The Friday decision was reportedly taken after a group of protesting teachers attacked the offices of political parties in the southern state of Chiapas, burning items inside, and vowing to interrupt the voting process.

Mexico's Interior Department further announced in a statement that the deployment is "aimed at ensuring all Mexicans can go to the polls peacefully."

The statement underlined that troops would be deployed particularly to southern states and Oaxaca, where much of the violence and ballot burning had taken place.

The unrest, which came ahead of the elections on Sunday for legislative as well as state and city offices, has so far claimed the lives of three candidates, one would-be candidate, and at least a dozen campaign workers or activists, according to local news reports.

However, unlike recent years when the violence appeared to come mostly from drug cartels, radical movements are now posing the greatest threat.

Extremist members of a teachers union on Friday burned or attacked the offices of five political parties in Tuxtla Gutierrez, the capital of Chiapas. They reportedly broke into the offices, ransacked the contents — computers, paperwork and furniture — and burned it in the street.

There have been anxious moments in recent days as army and police officers clashed with protesters intent on breaking into electoral offices to burn ballots.

The teachers have issued ambitious demands, such as 100 percent pay hikes and the end of a constitutionally-mandated teacher evaluation system.

In the colonial city of Oaxaca, teachers have burned ballots and blocked gasoline distribution facilities. Their leaders told local media they would block elections, even if they got the pay hikes.

Electoral authorities, however, have said they will go ahead with Sunday's elections as planned, but that they do not wish to militarize the elections.

MFB/NN/HRB