The Japanese government officially asked Internet service providers in Japan to block access to pirated manga websites on April 13.
NTT blocked the sites on Monday as a “short-term emergency measure” until the Japanese government is able to establish new legislation regarding site-blocking, with subsidiaries NTT Communications, NTT Docomo, and NTT Plala also implementing the site blocking.
The government had stated earlier this month that it planned to officially ask the providers to block the sites.
According to The Mainichi Shimbun, the hit counts on the three pirated sites has increased since last August when the sites became more well known.