Police say violence and destruction broke out as officers worked to break up a party involving hundreds of people near the University of Colorado Boulder on Saturday.
Police say three officers were injured after they were struck with rocks and bricks. Boulder Police Chief Maris Herold said all the injuries were minor. However, one officer came close to sustaining serious injuries, but a gas mask protected the officer's face from a blunt object thrown at police. At one point, Chief Herold says about 100 people charged at officers.