"Kwak said they would use 'marine terms' when launching the rocks,
saying:
'Mitch would say things like, ‘contact left,’ before Joseph would throw the rock at a car on the left side of theirs.'
He said the rock which killed Bartell made
a 'very loud noise... like a rail gun' when it made contact with her windshield.
Koenig was described by a friend as someone who likes creating 'chaos' and would often act in a destructive manner.
'Joseph and Mitch were talking about them now being
‘blood brothers’
and they could never speak of the incident,'
Kwak added.
The three met up the following day to
'get their stories straight'.
They had thrown rocks at vehicles on about ten occasions since February.
Six other cars were damaged and two more drivers were injured on the night Bartell was killed."
A picture reveals the damage caused to Bartell's car during the attack.
According to the Jefferson County Sheriff´s Office, Bartell was talking on the phone with a friend while driving in her yellow Chevy Spark in Denver at 10:45pm when she was hit by the rock.
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