Law-enforcement officers are investigating the shooting of a truck driver in rural southern Missouri that occurred late last week, media outlets reported.

Amy Holder, 34, of Paris Crossing, IN, was behind the wheel and her husband, Travis, was resting in the sleeper berth when a bullet entered the cab and struck Amy’s head.

The shooting occurred near Bourbon, MO, a town that lies along Interstate 44 about 75 miles southwest of St. Louis – about two thirds of the way between that city and Rolla, MO.

St. Louis news organizations reported that since February of this year, glass has unexplainably shattered in nine vehicles in that 10-mile-long stretch of I-44 – at least two of them tractor-trailers, and by one count at least eight in Crawford County. Officials did not find evidence in the previous cases of gunfire, but some sources now say a sniper may be involved.