Colorado Teen Pleads Guilty in Deadly Rock-Throwing Spree That Killed 20-Year-Old Woman

19-year-old Zachary Kwak from Arvada, Colorado has pleaded guilty to one count of first-degree assault, one count of second-degree assault, and an added count of criminal attempt to commit assault, in connection with a deadly rock-throwing spree that led to the death of 20-year-old Alexa Bartell.

Teen kills female driver in Colorado

The incident occurred on April 19, 2023, when Kwak, along with Joseph Koenig and Nicholas "Mitch" Karol-Chik, threw rocks at six different vehicles, resulting in injuries to multiple drivers. The fatal blow was struck just before 11 p.m., when Bartell, who was driving and talking on the phone, was hit by a rock while on the 10600 block of Indiana Street. The impact caused her vehicle to veer off into a field.

As part of a plea deal, Kwak will serve a minimum of 20 years but no more than 32 years, with his official sentencing scheduled for September 3, 2023.

A witness testified that after striking Bartell's vehicle, the suspects turned back to observe the damage and even took a photo of the victim's car as a "memento." Additionally, one of the individuals allegedly referred to the group as "blood brothers" upon realizing Bartell’s fate.

Investigators used cellphone data to track the suspects, eventually identifying Kwak and Koenig as the individuals responsible for throwing the fatal rock. Kwak, however, maintained his innocence during interviews with detectives.

Bartell’s family was present in court during Kwak's guilty plea, visibly emotional throughout the proceedings.