DENVER (CBS4) – Two groups are demonstrating in downtown Denver on Sunday with opposite messages. Many gathered at the Greek Amphitheatre in Civic Center Park to show support for law enforcement, while a few hundred people in another group gathered at the State Capitol steps to protest police brutality.

That group, led by the Party of Socialism and Liberation, vowed to break up the pro-police rally.

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Anti-police demonstrators march near pro-police demonstrators in Denver. (credit: CBS)

As of 3:15 p.m. both demonstrations have remained peaceful, however minutes later the opposing side made its way into the amphitheatre and into the crowd.

CBS4’s Rick Sallinger is amongst the crowd covering the story. He says the anti-law enforcement group banged on pots and shouted as they marched into the amphitheatre.

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Denver police officers moved in to separate the crowds as numerous fist fights broke out leaving several people bloody and injured.

(credit: CBS)

At least one person was arrested, while another person was helped out of the event.

The pro-police rally was hosted by the Becker Band and celebrated Colorado’s 6th Annual Law Enforcement Appreciation Day.

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Aurora Copwatch and Party for Socialism and Liberation organized the opposing rally.