Three vehicles were hit on I-10 on Saturday and another was struck on Monday.
Four vehicles have been shot at on an Arizona highway since Saturday, officials said – sparking fears of a sniper along the route.
Three vehicles were hit on I-10 on Saturday and another was struck on Monday. In three of the cases, the cars' windshields or passenger windows were hit. In the fourth, a headlight was struck.
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The Arizona Department of Public Safety is now trying to determine if the shootings are connected.
A 13-year-old girl sitting in the front passenger seat of a car suffered a cut to her ear when a bullet pierced the windshield on Saturday morning. She was treated at the scene.
Six minutes after that incident, another vehicle was hit.
Officials said it appears that multiple rounds were fired at each car.
"We are piecing together the story," said Arizona Department of Public Safety Director Frank Milstead. "What we are really asking is the public's help to be a good witness while we further investigate all of the evidence."
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Investigators are asking anyone with information to contact DPS on 602-223-2212.
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