It didn't mention in the article that the treat was written mentioning High School students. In my son school only the high school department was allowed to go home early and the younger students stayed because they were not included in the treat. They sent a message that they tightened security for the remaining children on the school.
They surely have sophisticated bombs in Japan when explosion artifacts flying through air hit only high school students and avoid younger kids.
"Fax machines are still commonly used in Japan."
such a lazy piece tacked on at the end. they always say these things when it comes to Japan. but guess what my bank told me to use when the Javascript on their website stopped uploading documents...
They should also mention Japan loves IC card reader on your PC when you are transacting online on government websites.