BERKELEY, Calif. (KGO) -- Some call it a group, others call it a tactic but regardless, Black Bloc caused a lot of damage at U.C. Berkeley Wednesday.
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Many blamed violent protests on campus on a small group of demonstrators and their military-style tactics.
Swarms of people dressed in black unleashed chaos on the campus, invading what was billed as a peaceful protest against right-wing commentator Milo Yiannopoulos.
"They asked Black Bloc to stay non-violent," said U.C. Berkeley professor Katrin Wehrheim. She says student protesters made that request of the anti-fascist group, but it didn't happen.
The group smashed windows, tossed smoke bombs, set fires and fought with police. The event was quickly canceled.
Student Chris Vinan said, "It was very organized and thought out."
Most recently, Black Bloc has launched protests opposing Donald Trump. The group began protesting in Europe in the 80s demanding a new world order. It first gained attention in the U.S. in 1999 during violent protests at a meeting of the World Trade Organization in Seattle.
Hundreds of Anarchists were arrested in the rioting, now the movement may be experiencing a resurgence.
"They're an organization we need to reckon with," said Wehrheim "Like the alt-right there are people who are part of the anarchist spectrum who are in too much pain to think rationally. They will do damage."
The university has condemned the violence, and admit police were not prepared for the onslaught. Authorities are reviewing surveillance video hoping to identify suspects and make arrests.
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