Pittsburgh police arrested a 22-year-old woman on the North Side yesterday after she left her baby in a car with the engine running while she went to buy drugs.

Shannon Elizabeth Bozel left her child in her car in Northview Heights while she purchased some heroin in the 200 block of Essen Street. Shortly after returning to her car and driving away, she struck another vehicle, police and emergency dispatchers said. The owners of the other vehicle called 911, dispatchers said.

Police found three stamp bags of heroin in her car.

Ms. Bozel was charged last night with possession of a controlled substance, endangering the welfare of a child and driving with a suspended license.

Police placed the 14-month-old boy in the custody of a grandmother.