high school student delivered himself with bringing his mother's head

delivered himself to the police for murdering with bringing his mother’s neck. He was only 17 year old and his mother was 47 year old. He said that he had killed his mother so the police searched his house. When police went to see his house, there was his mother’s dead body laying without her head which was cut by him before he came to police. Then Wakayama police finally arrested him for murdering. What he said after arresting was that he hopes every single terrorism or war would not happened. Also he said that it did not matter who he was going to kill.
Wakayama prefecture found out the student did not go to school everyday and his mind often goes out of mind so he did have some medical treatment. Police revealed that he came to police by himself with his mother’s head and said that he killed her midnight of 14th. He seemed very calmly when he was having investigation.