Copy-Trump protesters, supporters get into violent clash in Berkeley, CA

BERKELEY, CA (KGO/KRON/CNN) - Two groups clashed in Berkeley, CA as anti-Trump protesters showed up for a scheduled pro-Trump rally. Fireworks, bottles and traffic cones were thrown as the confrontation turned violent.

Police say 21 were arrested, 11 injured and seven taken to the hospital.

Many of the protesters covered their faces, dressed in all black. A mesh barrier meant to separate the two sides quickly fell down. Protesters began pushing, shoving and hitting people on the opposite side.

Police say they confiscated flag poles, a knife and a stun gun, and eventually police used pepper spray to get the crowd under control.

This isn't the first time Berkeley has seen a protest turn violent this year. In February, protesters caused more than $100,000 of damage after a night of violent protests against the appearance of right-wing speak Milo Yiannopoulos.

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