https://www.cbsnews.com/colorado/news/alexa-bartell-murder-arrests-arvada-rock-throwing-attacks-colorado/
(with photos)

By Jesse Sarles.

Three suspects were arrested overnight in Arvada in connection with last week's rock throwing attacks that killed 20-year-old Alexa Bartell and injured others. The suspects -- Joseph Koenig, Nicholas "Mitch" Karol-Chik and Zachary Kwak -- were arrested at their homes.

"We have a safer community this morning because of it," said Jacki Kelley, spokeswoman for the Jefferson County Sheriff's Office.

Authorities in Jefferson County say those arrested are all 18 year olds and all face first degree murder charges. They are seniors in high school. One attends Ralston Valley High School, one goes to Standley Lake High School in Westminster, and the other attends online school.

They will likely make their first court appearances on Thursday.

Bartell, of Arvada, was killed late at night on April 19 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.

Two other people were also hurt in earlier rock attacks that night. Seven vehicles in total were hit by what authorities now describe as "large landscaping rocks." It's believed the suspects were a in moving vehicle when the rocks were thrown.

"These suspects went from place to place to place to place throwing large rocks through windshields of vehicles. We have not seen this before," Kelley said.

The crime spree started that night shortly after 10 p.m. in Westminster at the intersection of 100th Avenue and Simms Street, just north of Standley Lake. The final attack was about 2 miles away and approximately 45 minutes later. That was the one that killed Bartell.

Investigators say the criminals were driving a black 2016 Chevy Silverado. They say they aren't sure if Koenig, Karol-Chik or Kwak was behind the wheel.

Kelley said the arrests came as a result of "cellphone device forensics and then supporting information from our public." She wouldn't elaborate on what that forensic evidence is, but she said more than 300 tips came in during the investigation.

"This information led us directly to them," Kelley said.

Initially the sheriff's office said Bartell's family was going to speak about the tragedy on Wednesday afternoon, but that news conference was canceled. Kelley said the family was grateful to learn of the arrests.

A memorial for Bartell with flowers and pinwheels now sits along a fence next to Indiana Street where she died.

More on it:

https://www.denver7.com/news/local-news/three-18-year-old-suspects-arrested-in-connection-to-rock-throwing-incident-that-killed-alexa-bartell