"This page seemed to have been around since a few years ago, and it appears that there were quite a number of people who posted each other this URL on some part

"This page seemed to have been around since a few years ago, and it appears that there were quite a number of people who posted each other this URL on some particular internet forums. It is still not clear why only these three were arrested by the Hyogo Prefectural Police under such circumstance. They may not have any specific reasons for that." Maybe the police only wanted to make an example of those three people and discourage the rest of posting the URL.