Must the heirs of one who died in a car accident—due to a tire exploding and the car swerving to collide with another vehicle, leading to his death and the death of others—fast sixty days, or free a slave, or feed sixty needy persons, or is there no legal obligation upon him?

If the driver did not cause the accident due to negligence, then nothing is incumbent upon him. But if he caused it due to negligence, then two things are incumbent upon him: the blood money (Diyya), which is borne by his 'Aqila (male relatives on his father's side), and expiation (kaffara), which is freeing a slave or fasting for two consecutive months. If the one who caused the accident dies, then what is incumbent upon him falls upon his heirs.