Prayut said investigation of the case had been completed.
Prasittichai Khaokaew, the director of a school in Singburi province, allegedly shot dead three people, including a child, while robbing a gold shop in Lop Buri province.
Among the nine charges Prasittichai faces are: stealing using weapons and vehicles causing others to die or get seriously harmed; possessing firearms and bullets without permission; using unregistered firearms.
The prosecutor has strongly opposed bail for the suspect and calls for a speedy trial since the case was of great interest to society.
Meanwhile, victims seeking damages have been advised to