Protesters commandeered a bus and tried to ram it through the gates of Oaxaca's state congress, in an apparent bid to show visiting federal senators inside that the rule of law has broken down in this picturesque colonial city.
The delegation of five senators from Mexico's three main parties arrived earlier Thursday to meet with Oaxacan officials, protesters and community groups over two days on a fact-finding tour to assess the situation in the embattled city, which has been paralyzed since May by protests and violence.
If they determine that the government has ceased to function, the Senate could vote to remove Oaxaca state Gov. Ulises Ruiz the key demand of the demonstrators, made up of a coalition of leftists and striking teachers.
The demonstrators were unsuccessful in their attempt to ram the bus into congress but did spray paint on the Senate commission's vehicle as it left, a day after protesters blockaded highways and tried to storm a government security agency, drawing scattered gunfire from police.
Officials said the resurgence in radical actions was an attempt to project an image of lawlessness and spark the ouster of Ruiz, whom they accuse of rigging his own election and using violence against demonstrators.
"We see yesterday's events as being orchestrated, but that isn't going to frighten us off," said Sen. Alejandro Gonzalez of the conservative National Action Party, referring to the Wednesday clash.
The senators met at a local airport with Ruiz and his cabinet, who have largely been displaced from their offices by the protests but claim the state government is still functioning.
More than 1 million school children have been shut out of classes in Oaxaca since the beginning of the teacher's strike five months ago, and many private schools have also closed their doors.
Also Thursday, at least 8,000 teachers in the neighboring state of Chiapas went on a three-day sympathy strike, leaving about 1 million students 40 percent of the state's enrollment without classes.
Most of the Chiapas' 40,000 teachers did show up for work, but the strike raised fears that the Oaxaca conflict could spread.