I found more of the story.
[snip]
Amy Holder, 34, of Paris Crossing, Ind., was shot near her left temple while her husband rested in the semi rig's sleeper compartment.
Holder, screaming and bleeding, managed to pull the tractor-trailer to the shoulder. Her husband drove to a nearby gas station and summoned police, Williams said.
A bullet fragment found in the truck - the first actual evidence of a shooting in any of the suspected cases - has been forwarded to the Missouri State Highway Patrol for testing, Williams said.
The worries parallel those earlier this year in Ohio, where authorities investigated more than 20 shootings - including one death - along a five-mile stretch of Interstate 270 in Columbus. A suspect arrested in March in that case has pleaded not guilty.
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