BERKELEY (CBS SF) -- A former Diablo Valley College philosophy professor has been arrested for his role in a violent melee that broke out during a Berkeley rally supporting President Donald Trump last month, authorities said Thursday.
Organizers dubbed the rally a "Patriot Day" for people who support the president, but it quickly degenerated into a brawl with counter demonstrators. Twenty people were arrested and 11 others were injured -- seven of which needed hospitalization.
RAW VIDEO: Protesters Clash in Berkeley (Profanity)
In the weeks since the rally violence, Berkeley police have gone through videos and photos taken during the event to identify others who may be charged with crimes.
SLIDESHOW: Images: Violent, Bloody Day In Berkeley
Authorities said Eric Clanton was arrested in Oakland on Wednesday afternoon. There had been an outcry for his apprehension on alt-right websites after a video clip was posted on social media of the 28-year-old allegedly assaulting a pro-Trump demonstration with a bike lock.
A DVC spokesman said among the philosophy classes Clanton taught was "Introduction to Ethics."
"We especially at Diablo Valley College received, in fact, hundreds of calls and emails concerning the hiring, that we have someone like this in front of our class, in front of our students, potentially dangerous," said spokesman Tim Leong.
Clanton was a candidate to teach another philosophy class at the college this summer. But he was arrested by Berkeley Police Wednesday.
Investigators said cellphone videos show him swinging the U-lock at multiple Trump supporters in the head, injuring at least three people.
Police said finding the U-lock attacker was such a priority, homicide detectives were assigned to the case.
"You're swinging a small metal object that can absolutely cause traumatic injuries," said Berkeley Police Lt. Kevin Schofield.
Investigators credit cellphone videos for helping them identify the U-lock attacker. Some people even posted their own research online, identifying the masked man as Clanton.
He was being held Thursday in the Berkeley city jail on $200,000 bail for assault with a non-firearm deadly weapon with an enhancement clause charge.
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