CNN says South Korea’s National Security Law remains powerful in the nation and is used to persecute dissidents and suppress freedom of speech, introducing cases of the persecution.

The online site of the U.S. broadcaster said on Wednesday that a South Korean man was indicted and jailed for re-tweeting messages from North Korea’s official twitter feed.

CNN said that the number of people who were prosecuted for charges of pro-North Korean online postings stood at five in the first year of the Lee Myung-bak government in 2008, but then jumped to 82 in a matter of two years.

The broadcaster quoted human rights groups from South Korea and abroad as saying that the controversial National Security Law is used to oppress political dissidents and restrict the people’s freedom of speech.

CNN also quoted a South Korean journalist as saying that the Lee administration is being criticized for interfering with the freedom of the press. The broadcaster also noted that of the four major media networks that went on strike earlier this year, two have resumed work while about a thousand journalists continue with their protest.