A large party with an estimated 800 to 1000 people raged for several hours before police were able to disperse the crowd who flipped a car and set off fireworks.
The gathering, believed to be made up of mostly students from the University of Colorado in Boulder, quickly grew out of control on Saturday night (local time) as partygoers ignored social distancing.
Social media began to flood with video and images of the party about 7pm, with police announcing on Twitter they were aware of the gathering and people participating could be subject to arrests.
"Hey boulder, what is wrong with you? [I'm] Ashamed to be associated with this school and town," one Twitter user wrote along with an image of the packed party.
"Looks like Boulder is going to be online education for a couple of weeks," another student wrote.
Shortly before 8:30pm a Boulder police SWAT vehicle arrived and began telling those gathered over the loud speaker to disperse or face “arrest”, “tear gas” or “use of force".
While some people could be seen in social media vision leaving as police arrived, others stayed and it is alleged officers were hit with bricks and rocks, causing significant property damage.
University of Colorado condemns alleged violence at party
Police spokesperson Dionne Waugh told Fox 31 detectives were reviewing a large amount of video evidence of the incidents with the goal “to charge and identify” individuals involved in the destruction.
It’s reported a fire truck and an armoured police vehicle sustained “heavy damage”, the spokesperson said.
In a statement on Twitter the Boulder Police Department said body worn camera footage and social media photos and videos were being reviewed to identify individuals who assaulted first responders.
“Detectives will review every lead we have to identify and arrest those responsible for this reprehensible and unacceptable behaviour,” Chief Maris Herold said.
The party happened one day after the city of Boulder held a memorial ceremony to honour and reflect on the nearly 6000 Coloradans lost to Covid-19 since the first confirmed case in the state.
The University of Colorado Boulder also issued a statement, saying any students found to have engaged in acts of violence toward first responders would "be removed from CU Boulder".
“We are aware of a large party on University Hill on Saturday evening and allegations of violence toward police officers responding to the scene.
"We condemn this conduct. It is unacceptable and irresponsible, particularly in light of the volume of training, communication and enforcement the campus and city have dedicated to ensuring compliance with Covid-19 public health orders.
"CU Boulder will not tolerate any of our students engaging in acts of violence or damaging property.”
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