More on Oaxaca disturbances: Who's the aggressor, Cué or SNTE section 22?

In Oaxaca, the "dissident" Sección 22 of the SNTE teachers union, which was engaged in violent clashes with the police, arranged a march through the streets of Oaxaca city that according to its own reports drew 70,000 (according to police 20,000), and demanded an apology from governor Gabino Cué, and the resignation of three members of his cabinet.

The demands were ostensibly due to the violent attack on Section 22 during President Felipe Calderón's visit here two days ago, where 20 people were injured, including 15 police.

Repeat: Out of 20 injured, three quarters were police, which were violently attacked by the "teachers.

I put this in quotation marks as it is well known, as Carlos Marín also notes today, a big chunk of them have never set foot in a classroom yet remain on the payrolls of the state of Oaxaca - a state that, to be sure, ranks near the bottom in terms of educational achievement. Yesterday's march certainly didn't help in this regard: Given that their teachers were busy marching, school was canceled yesterday for Oaxaca's 1.2 million students.

Be that as it may: I also noted another story on the violent clashes demonstrators-police, from Milenio. In a rough translation, here is a section of it that I found particularly telling:

The event that was scheduled with President Calderón at the Government Palace lasted barely half an hour. At that time, the head of state public security, Marco Tulio Lopez, tried to mediate, but was attacked. He carried a shield and tried to get close to have a dialogue, but he was disarmed and beaten. Protesters covered with scarves seized and held him. His bodyguards tried to rescue him, which started a second clash that left more injured, including the former member of APPO, Marcelino Coache. During the clash the teachers took three policewomen hostage, who were moved to one of their union headquarters. Later they were rescued by police. Some police cars were destroyed, and a bus was burned. 

Azael Santiago Chepi, head of Section 22, argued that their demonstration on Tuesday was pacific, but that  they were attacked by the police. With three police hurt to every wounded teacher, for being school teachers, they sure knew how to defend themselves.