HOWELL, Mich. -

A man charged with firing a gun at vehicles along the Interstate 96 corridor in Michigan says he did so because he believed motorists were part of a government conspiracy against him.

Raulie Casteel testified for more than two hours Monday morning at his trial in Howell.

The 44-year-old defendant told jurors he was filled with fear and anxiety while in traffic, most likely from an undiagnosed delusional disorder. Casteel said he never thought about the ramifications of the shootings, only that he wanted "to send a message to back off."  

Casteel is contesting terrorism and assault charges in connection with the two-dozen shootings in October 2012. Police say they matched his gun to bullet fragments recovered from vehicles.

Special coverage: Michigan Roadway Shootings

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