YAMAGUCHI – An 18-year-old male high school student under arrest for throwing a homemade bomb into a classroom Friday was targeting a specific student, according to police sources.
Police found out that the glass bottle used for the explosive contained dozens of small nails and other metal objects — apparently to make the bomb more lethal, the sources said Saturday.
Police also seized another bomb the boy had made, the sources said.
A total of 58 students were injured when the bomb exploded at Hikari Senior High School in Hikari, Yamaguchi Prefecture. Most of the injuries were minor.
The bomb burst into flames and exploded with a loud bang as it landed just in front of the teacher’s desk, spraying the classroom with glass and nails and spreading white smoke, according to witnesses.
Students were taken to hospitals for cuts as well as nausea and eye and ear pain. One student suffered a broken finger.
Police plan to examine the evidence further to determine how powerful the bomb was, and may consider serving a fresh warrant on the teen for attempted murder, the sources said.
The suspect, whose name is being withheld because he is a minor, reportedly told police he had a grudge against a group of students who had teased him about his shyness.
The police suspect that a seething resentment led him to throw the explosive at the seat of one of those students, the sources said.
Officials of the school said Friday they do not think the boy had been a victim of bullying. However, some students said the boy kept to himself so much that he was often the target of teasing, although they said they did not believe it amounted to bullying.
Police are now questioning the student to determine the precise details of the incident, including how he made the bomb, they said.
He has reportedly told investigators he made it himself.
Police suspect he used gunpowder from firecrackers and a soft drink bottle, and followed instructions from a Web site to make the crude bomb.
There are large numbers of Web sites carrying bomb-making instructions, and suspects in several recent cases have told police they learned how to make bombs on the Internet.
Investigators have collected a lighter from the scene, which they believe the boy used to light the fuse.
Police have also found a black toy gun near the scene where the boy was placed in custody, and suspect he may have been carrying it when he threw the bomb.