As of 2010[update], there are 65 North Korean-run and pro-North Korean websites blocked in South Korea.
[2] Blocking is based on the National Security Act, and coordinated by the Korea Communications Standards Commission, which also engages in Internet surveillance.
[5] South Korean law imposes punishments up to seven years of imprisonment for attempting to access blocked sites.
[3] Internet Archive's Wayback Machine and web caches of search engines are not blocked and include copies of North Korean websites.
[1] Twitter, however, has proven impractical to censor because retweets of North Korean tweets by other users are not blocked.