Prosecutors on Wednesday charged a 61-year-old Kapolei man for allegedly hitting his 25-year-old son, sending him to the hospital.
Edwin Fernando was charged with second-degree assault for striking his son on Monday.
Police said the two had been arguing, and the father hit the son, causing substantial bodily injury.
The son was treated and released at a nearby hospital.
The son reported the assault to police Tuesday, and police arrested him. Bail was set at $15,000.