Colin Gray, the father of the teenager accused of killing four people at a Georgia high school, knew of his son’s deteriorating mental state and his fascination with campus shootings, investigators testified Wednesday during a hearing that elicited troubllng new details of what led up to the rampage.

A grand jury handed up charges against a 14-year-old who is accused of killing four people at his high school. His father is accused of giving him access to the murder weapon.

A Georgia grand jury indicted a father and son on murder and other charges Thursday in the mass shooting at Apalachee High School in Winder, Georgia, last month that left four people dead and another nine injured.