Colorado Woman, 20, Killed After Cops Say Teens Threw Rock at Her Windshield

Police say they don't have a motive but made a point of saying this was not part of a social media challenge.

A 20-year-old Colorado woman was driving home from work when out of nowhere a rock came crashing into her windshield and killed her instantly.   

However, authorities say it was no accident. They say within 45 minutes there was a total of seven incidents of rocks thrown and now three 18-year-old high school seniors have been arrested and charged with murder.

Alexa Bartell was killed just outside Denver when the rock came crashing into her windshield at 10:45 p.m. She was on her way home from work and talking on the phone with a friend when suddenly it went silent.

That friend tracked Bartell’s vehicle to a field.

Authorities believe the suspects were on a rock-throwing spree and hit seven other vehicles within 45 minutes. They reportedly hurled huge landscaping rocks.

Uber driver Nathan Tipton is one of the victims and his windows were shattered by one of the rocks. He had just dropped off a customer minutes before being targeted.

Tipton made it out alive.

Bartell’s sister, Mikaela Marie, posted on social media, “Alexa was killed in a most senseless act by the hands of monsters who took her life by throwing a large rock at her car at high speed.

There are not enough human emotions or words to express the anger, the sadness, the pain, and the disgust I feel.”

Police say they don't have a motive but made a point of saying this was not part of a social media challenge.

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