Three teenagers charged in deadly rock throwing spree

Posted at 4:02 PM, April 26, 2023 and last updated 4:02 PM, April 26, 2023

By: Jeff Anastasio

JEFFERSON COUNTY, Colo. (KMGH) – Three 18-year-old suspects, all seniors in high school, were arrested in connection to a string of rock-throwing incidents at vehicles in Colorado, including the senseless attack that killed 20-year-old Alexa Bartell.

The Jefferson County Sheriff’s Office announced the arrests Wednesday morning.

Bartell was killed on April 19 around 10:45 p.m. after a rock was thrown into her windshield while she was driving northbound in Jefferson County.

The 18-year-old suspects were identified as Joseph Koenig, Nicholas “Mitch” Karol-Chik and Zachary Kwak. All were arrested at their Arvada homes, according to the sheriff’s office. They also confirmed that Koenig’s father, Mark Edward Koenig, was arrested overnight for allegedly obstructing officers as they tried to contact his son.

booking photos of (left) Nicholas 'Mitch' Karol-Chik (center) Joseph Koenig and (right) Zachary Kwak

Nicholas ‘Mitch’ Karol-Chik (left), Joseph Koenig (center) and Zachary Kwak (right) are charged with murder. (Jefferson County Sheriff’s Office via AP)

Announcing the arrests, Jacki Kelley, public information officer with the sheriff’s office, said the three suspects are seniors at different high schools but did not share which schools they attended.

She said the suspects were arrested in their homes, brought to the sheriff’s office Tuesday night and booked into the jail.

“This really came as a result of cell phone device forensics and supporting information from our public,” Kelley said.

She noted more than 300 tips from the public during the week-long investigation.

The three suspects face charges of first-degree murder related to Bartell’s death and additional charges are expected to be filed in connection to the other rock-throwing incidents, the sheriff’s office said.

Their first court appearance is scheduled for Thursday.

Investigators said Bartell’s vehicle was the last one in a series of vehicles to be struck by large landscaping rocks.

Her family was notified of the arrests early Wednesday morning.

“We were able to call them in the middle of the night once we had secured the suspects and brought them to the station. Those calls were made and they’re just so grateful,” Kelley said. “They’re still suffering from the greatest loss possible but this is the beginning of the journey that they’ll be on next and they’re incredibly grateful that these suspects are at least identified and brought to justice for what they’ve done.”

On Monday, two more people came forward to report they were victims in separate rock-throwing incidents on that same evening Bartell was killed.

A total of seven incidents were reported in Jefferson and Boulder Counties on April 19, all involving rocks thrown through vehicle windshields. In addition to Bartell, one other driver suffered minor injuries.

Bartell’s employer, Commercial Flooring Services offered a $15,000 reward for information in honor of their “youngest, brightest employee.”

Bartell’s mother, Kelly, is also a CFS employee, the company said.

As flowers lined a broken fence near where Bartell was killed, friends shared their memories of a life cut short with KMGH.

“She was a friend to everyone and brought so much joy into everyone’s lives,” a friend who asked not to be identified said.

“She was a very big personality. Everybody loved her,” Bartell’s friend Samantha Motisi said during a visit to a makeshift memorial Saturday.

This story was originally published on April 26, 2023, by KMGH in Denver, an E.W. Scripps Company.