Joseph Koenig, Nicholas ‘Mitch’ Karol-Chik and Zachary Kwak were taken into custody at their homes overnight

The high school seniors, all 18, are arrested for killing a female motorist by throwing a huge rock that smashed through her windshield

Alexa Bartell, 20, was killed when a rock crashed through her car windshield around 10.15 pm on April 19, in Arvada, Colorado

Bartell was on the phone with a friend, who traced her phone and found her dead

Suspects are facing charges of first-degree murder with extreme indifference, additional charges are expected

Victim’s car was one of a series of vehicles targeted in the week, during which several motorists were injured

Motorist Alexa Bartell, [photo], 20, was killed when a large rock crashed through her car’s windshield on April 19 in Arvada, Colorado. Authorities have arrested Nicholas Karol-Chik, Zachary Kwak and Joseph Koenig for murder in her death 

Three high school seniors are facing murder charges for throwing large rocks at cars, including one that killed a 20-year-old driver on April 19. 
The suspects, all 18-years-old, have been arrested for throwing large landscaping rocks toward at least seven cars on Colorado roads last week. The last of the seven incidents claimed the life of Alexa Bartell. 
Bartell had been speaking to a friend on her cell in Arvada at 10.45pm when she suddenly stopped talking. 
The concerned friend tracked the location of her phone and found her already dead, having been fatally injured by the hurled rock going through her windshield.
The susspects Joseph Koenig, Nicholas ‘Mitch’ Karol-Chik and Zachary Kwak were taken into custody at their homes in Arvada overnight and are all facing charges of first-degree murder, with extreme indifference, according to the Jefferson County Sheriff’s Office.
Authorities said additional charges are expected.

Nicholas Karol-Chik, [left] Zachary Kwak and Joseph Koenig [right], all 18-year-old high school seniors are facing charges of first-degree murder, with extreme indifference, after throwing a rock through Bartell’s windshield

In a statement, authorities said Bartell’s vehicle was the last of a series of vehicles struck by large landscaping rocks in a spree that began shortly after 10pm. 
She was driving on Indiana Street in her yellow Chevy Spark when a rock crashed through her windscreen.  
Since then, investigators have worked around the clock to identify and arrest the suspects responsible for her death, it said.

Bartell’s windshield was completely destroyed after the rock allegedly thrown by the suspects crashed into her car

It is not clear which suspect or suspects were driving during the spree, authorities added.  
‘Ultimately, mobile device forensics and supporting information from the public helped lead to the identification and arrest of the suspects. 
‘Investigators were glad to be able to notify Alexa’s family and the other victims of these arrests. This week’s recognition of Crime Victims’ Rights reminds us of the courage and resilience of crime victims, including the Bartell family. They are our motivation,’ the statement read. 

Bartell was driving the Chevy spark [photo], around 10 pm on April 19, when a rock came crashing through the front windshield. She was killed

Bartell swerved off the road after the projectile crashed into her subcompact sedan, with devastating effect

In the hour before Bartell’s death, six other cars had rocks – a type commonly used in landscaping – thrown at them.
According to authorities, two of the drivers suffered minor injuries. Lyft and Uber driver Nathan Tipton was uninjured after being targeted. 

Authorities said investigators have worked around the clock to identify and arrest the suspects. A $17,000 reward had previously been offered for information in the case

Speaking to reporters at a news conference on Tuesday, he said he was headed southbound on Highway 93, close to the Jefferson County and Boulder County lines, at around 10.15pm on Wednesday.
‘I saw two vehicles going northbound, but all I could see was the headlights, it was a dark road,’ he said. ‘And then a large shatter – it sounded like a shotgun blast. It scared the heck out of me.’
He said he pulled over right away and saw that both driver-side windows of his mini van had been shattered.  
‘It’s horrible. Nobody should lose their child for a random act of whatever this is,’ he added. 
A $17,000 reward had previously been offered for information in this case, according to the sheriff’s office.