Authorities said both victims were in a vehicle that was stopped Saturday afternoon when a suspect approached them on foot and shot into the vehicle.
Police say the motorist drove a short distance before coming to a stop, and the suspect fled in a separate vehicle, the Associated Press reported on Sunday.
Medical personnel pronounced the man dead at the scene. Police said the boy had a gunshot wound to his shoulder and he was taken to a hospital, where he was in surgery Saturday evening. His condition was not known.
Authorities have not released the victims' names.