By Conor McCue

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.

(credit: Major League Liberty/Facebook)

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.

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

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While many were fistfighting, 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.

“You see some of the images — somebody with an American flag poking at somebody else who’s in a fight with somebody,” said Chief Jeff Swoboda. “What kind of cowardly act is that?”

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

“If there are people out there claiming to support the police but go out there in a manner that’s not consistent with our values — our values of respect and integrity and service — that T-shirt doesn’t buy you the respect of police departments. We don’t want your support if that’s the way you act out there,” Swobota said.

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On Monday afternoon, Fort Collins police said they are planning to make more arrests in connection with the violence over the weekend. Those suspects have not been named.

Conor McCue