POTTSTOWN, Pa. (CBS)–The Montgomery County District Attorney and Lower Pottsgrove Police Chief announced the arrest of Donna Engler for Involuntary Manslaughter and Careless Driving for unintentionally causing the death of Shirley Wilhelm of Pottstown.

On the morning of September 9th, the defendant was driving a school bus at the intersection of Mervine and Charlotte Streets in Pottstown.

While making a right turn at the intersection, the defendant struck and ran over Shirley Wilhelm, who was a pedestrian crossing Mervine Street.

The victim died at the scene. Shirley Wilhelm was 78 years old when she was killed (See Related Story)

Based upon an extensive crash reconstruction it was determined that there were no obstructions to the defendant seeing Wilhelm crossing the street.

Based upon the fact that the defendant should have seen the victim and because the pedestrian has the right of way, it was determined that the defendant had driven in a careless, reckless and grossly negligent manner, which constitutes the crime of involuntary manslaughter.

This morning the defendant turned herself into authorities and was arraigned by a district judge.

Her bail was set at $25,000 and she was released on her own recognizance under the condition that she may not drive a school bus.

Shortly afterward, she waived her preliminary hearing, so the case will be sent to the Court of Common Pleas for disposition.