Murder charges filed against 3 defendants accused of rock-throwing incidents

Formal charges have been filed against the three defendants in a series of rock-throwing incidents that led to a woman being killed. 

There was no need to read the charges in court. The three defendants had already been informed. 

Each face 13 counts, including first-degree murder, attempted murder, assault and attempted assault. The trio remains in custody with no bond. 

Family members and friends of 20-year-old, Alexa Bartell, were in the courtroom. The woman was killed when a rock went through her windshield.

And on the other side, the parents of defendant, Nicolas Karol-Chik, looked at their son with tears in their eyes.

It was two weeks ago when rocks were thrown from a passing vehicle at seven cars in northern Jefferson and Boulder counties that were struck. 

The three were arrested after investigators used cell phone data and help from the public. 

A friend told investigators they were loading rocks into a truck at Walmart. 

In court, Karol-Chik, Zackary Kwak and Joseph Koenig answered "yes, your honor" when asked if they agreed to delay their preliminary hearing.

The three are due back in court on May 16 for their next hearing.