"Hit-and-run causing death" can be divided into "active escape" and "passive escape"
Active escape refers to the victim's escape after active behavior, while passive escape only refers to simple escape behavior. Only passive escape is a traffic accident.
In this case, Zhang had previously injured the young man, which constituted a traffic accident. However, the act of putting him in the car and leaving him behind is obviously an active escape. It should be considered as intentional homicide. Because Zhang's act of throwing the young man at the construction site was intentional, that is, letting the young man die, which objectively conforms to the constituent elements of intentional homicide. At this point, this behavior can not be evaluated as the aggravation of traffic accidents, but as intentional homicide.