Twelve people went to the hospital with injuries, one was admitted, and two people were thrown through a downtown business window, according to police and Poudre Valley Hospital officials.
"People were picking up bricks, throwing them at cop cars," said Tarah Johnston, a Fort Collins resident who witnessed the riot.
Fort Collins Police say it all started when two men got into an argument at the 100 Octane Bar and Grill in the heart of Old Town Fort Collins after the New West Fest and an Earth, Wind, and Fire concert.
"Once out in the square, the staff members pointed them out to us," said Fort Collins Police Officer Bob Younger. "...And exactly that same time they started physically fighting."
That's when Younger said the crowd got out of control, causing damage to businesses and at least four police cars.
"The crowd which was in the square, which was probably about 1,000 people at the time, became aggressive toward the police officers and started encroaching on the police officers," said Younger.
Police fired rubber pellets, and tear gas into the crowd. They also made announcements over loud speakers to tell people to go home.
However, at least one woman in the crowd said she saw too much aggression from Fort Collins Police when they fired the rubber pellets into the crowd.
"They were out of hand, they were crazy," said Johnston. "I don't blame them because people were antagonizing them. But to be shooting people right and left for no reason, people walking out of restaurants, not knowing what was going on. They were out of hand."
"That's a shame she has that opinion," he said. "I was there, I saw the officers. We were very professional. We were very courteous in a lot of situations."
Two people were thrown through Bob Criswell's pottery shop window on College Ave. They were taken to the hospital.
Police issued several citations for disorderly conduct and fighting in public.
"It definitely was something that I think was unfortunate that it happened," said Younger.
"But I'm glad we had the training we did to be able to handle this responsibly."
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