PLEASANT HILL, Calif. (KGO) -- Students from at least three high schools in the East Bay marched against President-elect Trump Thursday morning.
Sources say that two teachers got in the way of protesters on campus Thursday and walked away with minor injuries. The school district and police are not taking this lightly.
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The march may have started out as an exercise in free speech, but the demonstration that began at Concord and Mount Diablo High School Thursday has led to a police investigation after it briefly turned violent.
"There is a video I have not seen yet with regards to an interaction between non-students and our teacher," said Joseph Alvarez, a principal of College Park High School.
PHOTOS: Students protesting Donald Trump march through SF
Alvarez said a mob of protesting students from other schools broke onto his campus. Sources say that as many as six of those students punched and or pushed two of his teachers who had been opening an interior gate to let the marchers through. One of those teachers is well-known.
"He's a teacher that is beloved," some one teacher.
"I have accounts from the teacher and students. We are taking it seriously and looking at the entirety of the investigation," Alvarez said.
The march began Thursday morning and extended onto Concord and Pleasant Hill streets well into the afternoon.
"Our school decided to do a protest against Trump because he says he's going to deport people and says he is going to build a wall," said Justina Conn of Concord High School
Through most of the day the group was peaceful but loud.
"No one expected him to become President," said one student.
Nor did anyone expect a calm day on at least three East Bay high school campuses to turn into this.
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2 teachers injured as mob of students flood East Bay campus during anti-Trump protest