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1 of 3 suspects in Colorado rock-throwing death pleads guilty, sentencing set after other trials

1 of 3 suspects in Jeffco rock-throwing death pleads guilty, sentencing set after other trials
1 of 3 suspects in Jeffco rock-throwing death pleads guilty, sentencing set after other trials 01:25

One of the three suspects arrested and accused in last year's rock-throwing death of Alexa Bartell appeared in Jefferson County Court on Friday. Zachary Kwak pleaded guilty to three new charges in an agreement reached with the prosecution. 

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  Alexa Bartell  Alexa Bartell's family

In that agreement, the prosecution dismissed the original 13 charges, including murder and attempted murder. Kwak pleaded guilty to first-degree assault, second-degree assault and criminal attempt to commit assault. As part of the plea, the 1st Judicial District Attorney's Office said that Kwak agreed that he "acted knowingly, under circumstances manifesting extreme indifference to the value of human life, by engaging in conduct which created a grave risk of death."

Bartell's family did not make a statement in court, instead stating they would like to address the court at sentencing. Prosecutors told the court that Bartell's family did agree to the plea deal. 

Kwak and the other two defendants appeared in court just last month where they all pleaded not guilty to more than a dozen charges. 

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  Zachary Kwak Jefferson County

Twenty-year-old Bartell was struck and killed in April of last year after she was struck by a rock that was thrown into her windshield. Several others were injured in similar incidents with what authorities described as "large landscaping rocks."     

According to the plea agreement, prosecutors said they would accept no less than 20 years in the Department of Corrections for Kwak and the deal also included an upper limit of 32 years in prison. The judge said the deal did not allow for sentencing in the youth offender program. 

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  Joseph Koenig Jefferson County

Joseph Koenig, Nicholas "Mitch" Karol-Chik and Kwak were arrested and charged in connection with the rock-throwing attacks that killed Alexa Bartell and injured several others early last year. 

Investigators believe there were a total of 10 vehicles involved in at least three different incidents regarding the suspects.   

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  Nicholas "Mitch" Karol-Chik Jefferson County

They will be tried separately with Karol-Chik's trial scheduled for June 7, 10-14, 18, 20-21 and Koenig's trial scheduled for July 19, 22-26, July 30 through Aug. 1. 

Sentencing for Kwak has been delayed until the resolution of the other two cases involving Karol-Chik and Koenig. That is likely to happen in September. 

RELATED: Timeline: A look at the Colorado rock-throwing attacks

Bartell, of Arvada, was killed late at night on April 19, 2023, when a rock crashed through her windshield as she was driving on the 10600 block of Indiana Street close to the Jefferson County and Boulder County lines. Her vehicle left the roadway and ended up in a field. She was on the phone talking to a friend when she was struck and the phone went silent.  

All of the suspects were 18 years old and seniors in high school at the time of their arrests last year. One attended Ralston Valley High School, one Standley Lake High School in Westminster, and the other attended online school.   

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