By Danielle Chavira

FORT COLLINS, Colo. (CBS4) – Dueling rallies turned violent in Fort Collins on Saturday. The violence ended with multiple people being arrested and detained by Fort Collins Police.

A pro-police rally gathered outside police headquarters on South Timberline Road. Counter protesters arrived, and tensions quickly escalated.

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“Both sides had active aggressors, and enforcement action was taken against people identifying with both groups,” police stated on Sunday. “Officers are reviewing video and actively working to determine who these people were so they can be held accountable.”

A large number of police supporters were seen on video clashing with counter protesters in a drainage ditch between homes, away from the main protests. It is not clear what preceded this encounter.

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It is also not clear which group the counter protesters were associated with.

While many were fist fighting, some were seen using objects, like a pole with an American flag attached to it and a baton, as weapons. Police then broke up the fight.

“Committing crimes in our community is not a way to support police. We stand for safety, period,” said Fort Collins Police Chief Jeff Swoboda.

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Anyone with more information is asked to contact Det. CJ O’Loughlin at 970-416-2571.

Danielle Chavira