Investigators confirm that same gun was used to shoot at 22 cars on Michigan highways.
Shell casings found in Perry, Michigan may represent the first big break in the case of mysterious shootings at vehicles on roadways near Interstate 96.
Police have a sketch of the suspect described as a young man with closely cropped hair who was driving a black sedan, possibly a Chevrolet, Oldsmobile Alero or Toyota Camry.
As of Monday evening, 22 shootings have been reported.
Ten have been reported in Wixom, 10 more in Ingham County, Oakland County, Livingston County, and two in Perry and Shiawassee County.
No one has been injured in the shootings.
Police are sitting at highway off ramps to deter the shooter and provide help if another shooting occurs.
School recesses have been canceled for Wixom's elementary and middle schools.
It has been unnerving for many who frequent the areas where shootings have been reported.
The communities involved are on edge, hoping everyone's luck holds out and no one gets injured.
Police say they are searching for a man using a semi-automatic handgun, not a rifle.
They are working to prove that all 22 reported incidents are definitely the same shooter.
They have the full services of the Michigan State Police Crime Lab along with their polygraph operator.
Federal investigators also are involved.
Police are throwing everything they can at this case to make sure no one gets injured.