Teen admits throwing large rock onto highway, killing 20-year-old driver

One of three Colorado teenagers charged in connection with a series of rock attacks that killed a 20-year-old woman last year has pleaded guilty to assault.

Alexa Bartell died on April 19, 2023, when a large rock was thrown through her windshield while she was driving on a highway in Jefferson County, Colorado, authorities said at the time. Several other cars were also hit by rocks in a series of attacks that night.

Joseph Koenig, Nicholas “Mitch” Karol-Chik and Zachary Kwak, all 18 at the time, were arrested in connection with the attacks and initially charged with murder, PEOPLE reported at the time.

CBS News, The Denver Gazette And The Denver Post All reported that Kwak, now 19, pleaded guilty on May 3 to first-degree assault, second-degree assault and criminal attempt to commit bodily harm. This was part of a plea agreement that resulted in his original charges, including murder, being dropped.

According to the media, the prosecution and defense agreed on a minimum sentence of 20 years and a maximum sentence of 32 years. Kwak will be sentenced after the trials of the other two defendants are completed, CBS reported.

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CBS also reported that prosecutors said Bartell’s parents have agreed to the plea deal and plan to speak at the sentencing hearing.

Online court records show Karol-Chik’s trial is scheduled for June, while Koenig’s trial is currently scheduled for July.

NBC reported last year, citing court documents, that the three teenagers allegedly returned to the crime scene after the stone attacks to take a photo as a “souvenir.”