AUGUSTA, Maine (AP) — The operator of a logging truck blamed for the death of a state trooper has been cited for several violations over the years.

The investigation into the death of Maine State Police Detective Ben Campbell is focusing on the truck that had two wheels fall off. One of them hit Campbell on Wednesday as he was assisting the operator of a disabled vehicle.

WMTW-TV reports that Federal Motor Carrier Safety Administration records indicate owner-operator Scott Willett had seven citations. Those include for steering system components that were worn, welded or missing. Last June, he was cited for a load that was too heavy.

State police spokesman Steve McCausland said the primary focus of the investigation is on the truck. An inspection of the vehicle will take several days.

More From